I'm 26 yrs old...smoking for about eight years now...I sometimes get terrible shortness of breath episodes...currently experiencing it now. I don't exercise. About a year ago I went to a pulmonologist, and had a lung function test done..which came back normal...have also had several tests done on my heart including numerous ekgs, halter monitor, event monitor for thirty days, and stress test....all normal. My doctor says that I have anxiety disorder, and am on Klonopin for that. My lungs burn so bad, i feel it in my chest and back...especially when I awake. Is there a chance that they missed something and I could have COPD or emphysema...am scared that I am going to die...PLEASE HELP!!!!