Hello Sir, This is Vijay. Sir I am 21. When I was 17, one night I slept on my forth close to the bed and my back on the upper side. In the next morning when I got up I saw a large amount of sperm had ejaculated out of my penis and my left testis had got swollen. That time it was painful. Within very few days, the size of my left testis was getting its normal size. But it do not got its normal size completely. Still it is a bit larger than my right testis. I masterbate twice in a week. I have no pain in it. But when I hit my both testicle with my hand, I get a slight more pain in my left testicle. During or after masterbation, I do not feel any pain but its size is a very little bigger than my right testis. Please help.