im 15 and have pains like a burning pain or a tightness pain in the middle of my chest , it start on the left but has spread to the middle. i am worried and don t want this to turn bad, i don t want to see a doctor about it i just want advice, and any info on what it could be, ive had this before and usually stretch my chest out to make it go away, somehow it does actually go away, but this one wont. by the way ive had it for 2 nights. please help ?