My pains and hallucinations.....?

I'm 17 male, and Iv been having pains for about 9 months now, Originally i thought it was my heart as it was around that area, as well being in hospital having my heart going 200 bpm. I think Iv figured it out, Its got to be anxiety and stress and depression going round in a circle. I play a y person and don't let my emotions show to others, but I think the pains is because I'm stressing out about the pains which are from anxiety which leads to being really depressed. Which then causes hallucinations and a voice in my head. All going round in a circle. I know I'm not mad whys I wouldn't gather these things. I do cut my self because it calms me down, strange technique I know but it does work for me. After it was my heart the problem I thought it could be my lungs but it can't be because it would hurt when I breath and it doesn't. I haven't been able to get my happy hard for months which is really annoying as my girl getting really annoyed so am I! My mood does change regulary, but I'm not bipoler or anything as I don't do anything that stupid im quiet sensible.What do i do?