Week-long trip to the UK. Help for an inexperienced traveller?

So I've been saving up to go on a trip and I've finally managed to get everything in order. I'm pretty low-maintenance and on a budget, planned to just stay a week in a hostel and take a few day trips out to different places depending on where I stayed. My only problem is that I've never flown anywhere and have only been to a few major cities, with none being quite as big as London, which is one place that I planned to spend a day or two (maybe even find a hostel there). I'm not really interested in the typical tourist attractions. I'm just looking to get away from home for a bit by myself and experience some new places.
I'm a college student and planned to take the trip in the week between my current term and this following summer term, which would be in early May. I have roughly $2,300 saved. As the general dates get closer, I've started looking up the prices and such and found that I'd spend around $1,000-$1,300 on the airfare and accommodation.

So my questions are:
Is there anything that I could be overlooking?
Would it be better for me if someone else comes with me, since I have no experience with major airports/cities?
Should I just hold off on the trip and go somewhere in the US instead?
Is there anything I should know that would make my flight less stressful?

Sorry if this is all just a bunch of irrelevant information. I just want to make sure that everything is covered.
Any help would be greatly appreciated.

You should definitely go, it sounds so exciting!  Britain has (generally speaking) a similar culture to the US, and speaks the same language, so it's perfect for a first trip abroad.  Having backpacked a bit, I'd say you don't need to have someone go with you (not that it would be bad if they did), since you'll meet people in the hostel. 

You might consider getting an Oyster card for the tube once you get there.  You have to put down a 5 pound deposit for the card (I think), but you can get that back when you leave and turn the card in.  It will make your tube journeys a lot cheaper. 

You may not want to make a detailed itinerary in advance if you want to go with the flow, but if you do, then you should think about booking train tickets in advance (for any day trips out of London) as it is usually quite a bit cheaper.

When planning trips, I tend to use the TripAdvisor forums and a good guidebook (Lonely Planet etc).  There are also backpacking specific forums which might be more helpful for you.  Good luck, and have a great time!

Definitely go for it! You won't regret it.  An overseas adventure is a great thing.  I was also going to recommend the Lonely Planet guide books.  Some prefer Let's Go, but I was always a Lonely Planet girl during my backpacking days.  Those two are generally the best for budget travel and hostel recommendations.

Concerning getting an Oyster in London - it really only makes sense if you're there for more than a few days or are only making a few journeys by public transport during the day. If you're staying within the first two zones of the city (which is likely for a tourist), then I'd recommend getting an off-peak day travel card for zones 1 and 2. You don't have to pay a deposit on these and the price is the same as what your Oyster card's daily cap is. Here's a comparison between the two:
http://visitorshop.tfl.gov.uk/help-centre/ticket-comparison.html

I'd recommend using an online page such as TripAdvisor for your hotel search as it's generally more up-to-date and thorough than a guide book (most guide books are in fact cutting back on hotel listings and replacing them with restaurant suggestions). Base your guidebook on what you want to get out of it. Do you want something that provides a lot of history? Do you want something with a lot of pictures to help you decide what you want to see? Or maybe if you don't need recommendations you just need something with a lot of practical info and some maps.

I'd personally recommend a DK Eyewitness book, partly because they're really good and partly because I work there and don't like seeing all these Lonely Planet recommendations! You can generally preview most book content online now before you purchase it as the travel book sector is becoming increasingly digital as fewer people buy the print book. Here's some of DK's London recommendations: http://traveldk.com/london

I'd personally recommend a DK Eyewitness book, partly because they're really good and partly because I work there

I didn't know you worked for them! How cool! I really like their books and have bought them for quite a lot of our holiday destinations!

I'd personally recommend a DK Eyewitness book

The diagrams and such in DK are very nice.

Thanks chary and sonofasailor! We put a lot of sweat and love into what we do, so it's great to hear people like and use our books.

Thanks for all of the help and links everyone! I've been really looking forward to this trip since I first started saving up. But I have one more thing that I forgot to mention earlier.

Being a college student at the moment, I'm still living at home with my mom. She can sometimes be extremely cautious about things and is concerned about me going by myself. She's explained that she personally wouldn't go on this trip alone, and she has travelled quite a bit.
I know that there is always a chance of getting lost, having items stolen, and much more. But those things can really happen in any large city. Is there anything that I should be really concerned about regarding these types of things?
Personally, I am aware that bad things happen to people on holiday. I expect things to not go completely as planned. I suppose I've just researched enough that I feel quite comfortable with being able to go on my own and handling any obstacles that come my way. Either that or that's just my ignorant lack of travel experience that's telling me that things will be fine.
But being that I haven't travelled much, I have no way to reassure her that things will be okay.
Can anyone figure a way for me to convince her that this trip isn't a complete waste of my time? She said that she obviously wouldn't be able to stop me from going, but she wouldn't be too pleased about me going while she's still worried about safety.

It's kind of fun traveling alone.  You get to do what you want, when you want to do it.  No checking with your buddy to see if they are hungry and how much they want to spend on lunch etc.  You get to meet new people from all over the place that you may not have bothered to speak with if you have a friend with you.

If your mom is worried, suggest that you get your cell phone all turned on to be able to make calls abroad and tell her you will check in once a day if she helps pick up the cost of those calls.  A 2-3 min call each day won't be super cheap, but if you keep it short, it shouldn't be too much.

I love to travel alone. But definitely, I would second the getting a phone that works in the country you're in.  (Though I don't always follow my own advice!)

As long as you're sensible (as you would be in any US city) you'll be fine. It sounds like a great trip and, as others have said, there are lots of advantages to traveling alone! I say do it!

Being a college student at the moment, I'm still living at home with my mom. She can sometimes be extremely cautious about things and is concerned about me going by myself. She's explained that she personally wouldn't go on this trip alone, and she has travelled quite a bit.

I first went abroad when I was 20 and my mother was really uncomfortable about it. The only reason I was allowed to go was because it was with a university program so she figured I would at least have some support in the UK instead of just being on my own. But fact is, I travelled a lot on my own without the university. So I can understand the problem you're facing. It's not so much that she thinks something bad will happen to you - it's the concern that she can't easily get to you if something does. I think if you can check in with her once a day, that will put her at some ease. Having an itinerary of places you're staying, flights and train bookings that you can pass onto her will help as well. Make a small card with important contact information (i.e. 999 for emergencies, the number of the American Embassy, National Rail Enquries if you're taking trains) and let her know you'll be keeping it on you at all times. Maybe even made a few of them to keep in various bags/clothes just in case.

An important thing for her to know is that London takes tourists' safety seriously, especially with the Olympics approaching. (In fact, I almost find the concern about safety here to be a bit on the extreme ends at times!) Police are regularly patrolling tourist areas, train stations, etc. and the majority of Londoners will be more than willing to point you in the direction of help if you need any, not to mention there are maps all along roads and tourist areas to help keep you from getting lost.

It's definitely a trip worth making. Good luck with all your planning! 

As the mother of a daughter around your age I can completely understand your mother's concern. I always worry when my daughter is out alone. I think the key is showing her that you are well planned, that she knows your plans as much as possible and that you have regular check in times with her to put her mind at ease. Do you know anyone at all in England that could me an emergency contact just in case?

Your trip sounds fantastic. You'll have a blast! Everyone has given great advice.

The two times I've been traveling outside of the US with friends, I had awful experiences (one left Australia 6 weeks into a year-long trip). I think traveling alone is a good idea as long as you are prepared and cautious! And definitely get a phone that works in the countries you are planning to travel in, so you can check in with your family back at home.

I'm glad to hear such positive things about my plans, everyone!
We're still going over my options and I think we've settled that she might go with me. The feedback about it being fairly safe have put her mind at ease about that, but now her concerns are being me getting lost or missing a flight because I've never been on a plane. Plus, she wants to go as well.

Anyhow, thanks for the advice everyone. All of this positive feedback has made me even more excited for May!