I am male 27 years, I do hand job and release sperm about thrice in a week. I am doing such practice from the age of 13 years, and now I feel my penis is not take so much growth and erection as my friends have and their is minor pain in testis after releasing, My penis is 2 inches in diameter and 4.5 inch in lenth, I am Asian and never sex with any women or girl in my life just do masturbation or hand job, but now I am curious about it, Does my penis be effected if it so, then how will it can be recover? plz help.