Little inflammation in holding urine.

After ejaculation, for a day or two, I feel inflammation and uneasiness to hold more urine as I used to. This goes with normal days too but inflammation is little less. The inflammation is more when I drink more water and bladder is full. Also I feel more gas in stomach. With more gas stomach is pressed and more uneasiness to hold urine. I was treated for recurring UTI two years back with 2 months of antibiotic course. The doctor doubted for prostatitis and then given me antibiotics. The problem persist from then only. I have been tested for usg whole abdomen(multiple times), urine routine and culture (multiple times) , PSA, and everything was normal. Can someone suggest what should I do?