This kind of sounds like my husband when he visited me for the first time in the US (in NC, in AUGUST, so 30-40C heat!). He didn't realise that we are forced to drive everywhere (7 miles from the closest town), how much land we have (5 acres), the sockets (in the bathrooms especially), how slow the broadband was, everything!
We joked about it and when he visited for the second time over Christmas that same year (and when we were married), it was better.
I had prepared myself with what to expect with moving to the UK as much as I could, but it was still a shock for most things.
'Very sweet' in my family means that you notice small things, do things for one another, make the other person feel very welcome, and that you're close to one another. So, it's a good thing. Unless she is extremely close to her mother, I wouldn't expect her to say anything more romantic in front of her. I know I wouldn't!