Around February 2016 I Was Practicing Very Hard For Americas

Around February 2016 I was practicing very hard for Americas Got talent. And one day I woke up my left arm felt numb and it was difficult to close my hands without my veins tingling. The pain also was felt under the side of my arm, top of shoulder, upper back part, and somewhat near the wall and lower part of my heart. Every time I exercise I easily get shortness of breath and the pain started to happen in which my hands would twitch and my arm tingling in the area of the vain. 11 months have passed and I have conducted all scans but the doctors can't find nothing wrong with me. One doctor said I exerted my muscles from over practicing. However, today this problem is not severe as it was before. But I still can't exercise because when I do the pain returns to my chest, upper back neck area, and a little bit feeling in my arm. So can anyone tell me what this is. I have a few suggestions but not sure which I think it could be : Angina pectoris or hypertrophic cardiomyopathy disease. So please let me know.