There are some forums about cutting..check on them. and hopefully some of the members will see this and respond....
teen years are the worst, raging hormones etc....Only a Dr. would really know if you have something wrong. I do think you should start with a therapist and be really honest about stuff. There are good people out there. This here is an excellent place to start as we have so many people here with a lot of knowledge and dealing with their own demons.

My demon has been depression, probably starting in High school but I lived along time ago where depression and anything "wrong" was not really recognised. I was not diagnosed with major depression till twenty years later.

I hope you find some answers. So glad you are here!!!