Hello, I Have Been Suffering From Chest Pains For About

Hello, I have been suffering from chest pains for about two years now. About a year and a half ago I was taken to the doctors and got my heart looked at and they said everything looked good. That those chest pains were most likely anxiety. I have really bad chest pains now and it has been going on four about an hour now after going to the gym. I did not do anything that could hurt my chest muscles while at the gym. These chest pains consist of pressure on my chest and tightening, it also hurts every time I breath. I have no idea what these chest pains could be but they are very painful.