night fallness problem from last 3 years

Hi Mohan, 

I believe you are referring to a "nocturnal emission" or a "wet dream."

These are NORMAL and many males, and some females, have them.  Basically, you have an erotic dream, get an erection, and have an orgasm.  You wake to sticky shorts.

Masturbation CAN reduce the frequency of these but may not eliminate them completely.  They show you are healthy.

Hope it helps.