Breathing problems associated with bloating?

A couple months ago I began having issues breathing. I could breathe but I felt short of breath and like my chest was tight. I felt like I needed to take a deep, deep breath constantly and after a while this started to cause severe pain in the center and side of my chest, I have panic attacks so I figured it was something similar to this and left it alone, hoping it would go away. It got a lot worse, especially since I was in Michigan at the time and it was extremely cold. (I've noticed that cold, sharp air aggravates it) I went to an urgent care place and had tests done. Everything from my heart, to my throat and my lungs, and they said it was a gastrointestinal problem, and I was given something for it. I also went to a physical therapist and after a while it went away. Now, its come back, though not as bad and it gets worse when I'm under stress. The other day, for about 5 minutes there was a stabbing pain in the center of my chest, worst than I had felt it EVER and wouldn't go away until I applied pressure there for a while. I was on the floor in a ball, it hurt that badly! I've had everything checked and it all seems normal, so what can I do to make this problem go away FOR GOOD? I'm 17 so my options are sort of limited but I would really like it to not be a hassle anymore.