Uti More Condition_symptoms I Have A Uti And I Was Wondering If It Could Be Something More Serious?

I have a uti and i was wondering if it could be something more serious? - uti more condition_symptoms

I went went to the doctor and had a urine test and told me that I have a urinary tract infection. I was prescribed the antibiotic Bactrim Bactrin or take 2 times daily for 1 week. I am on the fourth day and have not improved. My sides still hurt when I move or yawning, coughing or sneezing, and still hurts when you urinate. How long does it take for antibiotics to work? Could be more of a urinary tract infection? How could appendicitis?