What is this chest pain?

About 3 months ago I woke up with really bad chest pains, tightness, and pressure ( felt like someone was sitting on my chest constantly) after a day or two, I developed an aggressive cough. It lasted for about four days before I went to a walk-in-clinic and the doctor there barely listened to my symptoms and told me no information. He prescribed me the "Z Pack" and said I had bronchitis. In January, I was in Europe and the same thing happened again. I had no access to a Doctor there because I was on a school trip, so I dealt with it. When I got home 10 days later, it seemed to be a lot better so I didn't go to the doctor, although it took weeks to get back to normal. Now, I have the same chest feelings again but it has not developed into a cough yet. However, I can't do any type of activity (walking fast, running, going up the stairs) without it feeling like someone has my lungs in their hands squeezing them and someone is sitting on my chest. I might have ped out if I had to continue to run (in my cl). I don't think it's bronchitis. Anyone know what I might have?