If you're having mood swings due to racing thoughts pertaining to your carnal desires, you can always seek help.
I don't know how I could do that without embarassing myself or crossing the child-parent line. "Hey mom, dad, I kinda need some help and/or medical attention because I'm having severe mood swings due to giving up masturbation and carnal desires due to my new religion that you never really approved of." It just seems very odd to me.
Ask your guidance counselor at school for resources. Once a resource has been identified, then let your parents know.