Thanks for writing to Healthcaremagic. I have gone through your question and understood your query regarding size of your penis and perceived effect of masturbation on penis size. Masturbation is akin to sexual intercourse. What penis does in vagina during sexual intercourse, same it does during masturbation in your folded palm. If sexual intercourse does not reduces penis size, than how masturbation can do? Obviously NO. It is myth that masturbation causes impotency or reduce penis size. In fact, penis size or circumference has no effect on sexual satisfaction of either partner by penis vaginal containment. Only lower vagina (outer 1 and half inch only) has nerve fibers. Inner vagina is largely insensitive and lacks nerve fibers. If you want to arouse the partner during vaginal containment, you should focus only on outer vagina. For this erect penis size more than 2 inches is more than enough! Nothing is going wrong with you. Relax and wish you good sex life ahead.