Hi everyone! I am a 16 year old female, ive had to UTI in the last three months now, got prescribed trimethropon or something for both, it worked the first time but the second time (about a week ago) I've noticed that when I urinate I still have a slight burning sensation during and after just for a little, I am also still getting chills while I pee and I feel extremely sick with a sore stomach and back a lot. Should I go back to the doctor or is this just normal?