Re: Feels like I have to pee, but I can't?
I would never question your doctor, but most antibiotics are prescribed for 5 to 7 days usage. If your doctor is having a C & S (Culture and Sensitivity) test done, it will take at least 3 days for the results. Your doctor then can prescribe a more suitable antibiotic for you.
As stated by Bruno, drink plenty of fluids, especially water.