I'm only 14 but i have been expiriencing, ever since september 2014, a stabbing, squeezing, popping feeling in my chest right near my heart. This feeling occurs randomly and if i try to breath while the pain is occuring the pain becomes ten times worse so i tend to hold my breath until the pain goes away. I also have been expiriencing pains in the left side of my jaw, neck, and shoulder. I don't know if the two could be related or not. Some studies say that this is a cause of stress but i was wondering if it could be something else.