Increased frequency of micturition can occur due to infection, diabetes
, tumors in the bladder or prostrate, STD, excess intake of fluid, pregnancy, use of diuretics, stones in the urinary tract etc.
Reduced bladder capacity, masses in the bladder can also cause increased frequency and incomplete voiding.
I would suggest that you repeat a urine analysis with culture and cystometry with cystoscopy done.Get a check of blood sugars also.
Consult your urologist and discuss the possible options.