Swelling and tears of the Foreskin

Patient: Sometimes when i masterbate like if i do it several times in a week my foreskin will become swollen and there will be tears on the forskin itself. The penis does not hurt or anything but it is hard to pull back the foreskin because it is painful because of the swelling and the tears of the skin. At one time it happened but it took awhile before it was normal again (like months)Can u tell me what why this is happening and how or what i can use to make the swelling and tears go away?? Thank you. Eric.

Doctor: