Dear user, I understand your concern. Masturbation is akin to sexual intercourse. What penis does in vagina during sexual intercourse, same it does during masturbation in your folded palm. This is a natural activity and I would say a healthy activity and does not either affect or deter sexual performance. It is myth that masturbation causes impotency in future. Masturbation gives pleasure is natural thing. But if one has to do it against own wish (you want to control it but cannot) and associated with inappropriate excessive guilt, disturbance in daily routine or studies (as in your case) then it needs psychiatric evaluation. Have a talk to sex therapist or psychiatrist to clear your doubts. Pass some time with sports and your friends. Watch some good entertainment TV serials daily. Go for regular physical exercises daily like running, jogging, swimming etc. You will come out of this problem soon. Wish you good health.