HELP! 6Mo with UTI

I need advice/reassurance...
I'm 6 months pregnant and have a UTI. My back is killing me, I've thrown up 4 times on an empty stomach and have had diarrhea with a fever. I can't seem to keep anything down, not even water. I went to the dr and they wanted to do a culture to ensure that was it but went on ahead and gave me an antibiotic and something for the UTI itself. I feel horrible and I feel even MORE horrible that I'm sick with my little baby. He's still moving a lot but I just hate it that I haven't been able to eat and I am so dehydrated. 
Any tips or ideas of what's going on or what I can do to start feeling better sooner? Thanks in advance!