How To Treat Cracks Caused Due To Masturbation In Penis?

My penis foreskin becomes crack all around after musterbating and it hurts for about a few hours if touched by any object. However the cracks disappear after two or three days but I still can see some dull marks it left behind which i guess is not curing inside. If left untouch, the cracks don't seem to come back but, when i musterbate again after a few weeks, the cracks come back just as before... this has been happening for about five months now... what treatment should i take?