Talk to General Practitioner on Prone Masturbation

Sir I am doing prone masturbation for last years I left it in 2014 but from 2015 I am doing it on and off I leave it for sometime but go back to it I use hand as well for masturbation The other problem is that while I am laying down my penis in erection position touches my belly instead erecting straight Please help me out how can I recover from side effects of prone masturbation I will be married soon