I am a male.why I feel burn or somebody is poking knife in my bladder in the morning,i feel urgency to urinate.even if the urine output is less I feel urgency to urinate in the morning,if I don't urinate I feel like somebody poking kinfe in my bladder (extreme sharp pain),but I don't feel any pain white urinating ,i feel relief while and after urination.I masturbate a lot so I thought that my prostate was enlarged then I did ultrasound of full abdomen and prostate and no sign of enlarge prostate or any sign of stones in any part. Please any doctor can help.