It happens.. Dur to sensitivity and pleasure  issue..

due to hyperexitation, can be cured easily but take time, no sideeffects

I would like to suggest you a couple of exercises 1. While you are urinating, stop the urine mid steam for 2 seconds. This should be done by contracting the muscles and NOT BY USING HANDS. After 2 seconds, you should let the urine pass for next 5 seconds and again stop it midstream. This sounds simple but requires practice. This needs to be done each time you go for urination. Initially you may stop the urine only ones but gradually the frequency of stoppage can be increased. 2. While working or sitting at workplace or at home, contract (tighten) the pelvic muscles for 5 seconds and then release it for 5 seconds.  Now you would wonder where are these pelvic muscles are? If you are still confused about what are the pelvic muscles here is a clarification. Suppose you are standing in a queue outside a public toilet and you have go to pee in urgency and  You have to wait for 5 min for your turn. You would stop your urine in some way by making some muscles around your penis tight. These muscles are the pelvic muscles. Do such repetitions for 5 times continuously, and you can also repeat such sets 5 times  a day.