Drink a bunch of water or cranberry juice it might help flush things out. Your uti could be in your kidneys now and causing more pain. If it keeps getting worse instead of better (and your dribking lots of fluids) call and talk to a nurse for suggestions. A uti can go from a mild annoyance to omg this is horrible really quickly.
I found that cranberry juice (actual real cranberry juice) or dark cherry juice or even cranberry pills took the edge off utis quicker than antibiotics. Also having fluid to pee out is much better than feeling like you need to pee and not and it just hurting. Hang in there, give the antibiotics a bit of time to work