Aleanora,
I'm so sorry you are going through this pain.
I am in a similar situation minus chest pains, I had my twins in dec of 09, and about 6 months after their birth, i couldn't get out of bed, and in serious pain in my lower back and numbness/shooting pain in my right leg, which I now know is prolapsed disk, with sciatica. I've been suffering with this pain for many months now, I too have and still do sometimes struggle with just walking and don't leave the house much as walking is so painful.
I chose to breastfeed my twins until they were a year old so meds were a no go for so many months. I was in constant tears and finally was able to get in for spinal epidural. I had a series of 3 injections the first was the best, 2nd help, 3rd didn't work at all, I don't think the got the needle in the spinal cavity.
I don't have a clue if this is what's happened to you, But an Xray will not show a prolapsed disk or the sciatica, or if you have nerves being pinched or compromised, if that is an issue, must have an MRI to see that. So hopefully your request for MRI will go through.
I feel so bad for you, wish I could give ya a big hug.
After I stopped nursing the twin in Jan, Dr's tried prescribing me cocodamol, targinact, then stronger targinact, nothing touched the pain in my leg which was due to nerve pain, Finally the spinal department i am seeing suggested my GP prescribe me gabapentin, I'm on the lowest dosage, and thank goodness for this drug. The nerve pain isn't completely gone but I can cope much better now. I hate taking pills, but its a have to just cope day to day, especially caring for the twins. which they are full of beans now.
I am going to beg the spinal unit in Derby for spinal injections again next visit, so I don't have to take pills for a while.
I really am hoping things get sorted out for you quickly, its so completely demoralizing suffering day to day.
Your in my thoughts, keep pestering your GP till something happens.
Big huggles!