I am 16 years old, I'm relatively healthy, and i do exercise. But over this past week Ive been having chest pain, it feels like my chest is tightening up inside, and it is painful but not so that I am in constant pain it is more of an annoying pain, especially because i have it about 5-6 times a day. the pain doesn't last longer than 1 minute. i usually massage my chest and take deep breaths. I was wondering if it could be related to stress? Ive been having my exams recently, and revising is difficult for me, and on top of that I have boyfriend issues. Could anybody tell me whats causing this