I went through the same thing about 5 years ago.I was 35 yrs.old. I really know what you are going through. In the fall of 2003 I started noticing that I just couldn't take a deep breath, and I was breathing really shallow all the time. It was constant, not something that would come and go. I went to a respiratoy specialist, an allergist, and even to the ER once when I felt like I was at the end of my rope. All of my lung function tests were normal. Heart was normal. I felt like they all thought I was crazy because I still couldn't breathe right. The ER doc put me on 10 days of ativan. That didn't help either. I had an albuterol inhaler, advair 250 (for awhile it was Advair 500), theophylline, allergy medicines, and Prilosec just in case it had to do with acid reflux (which I did not have). Nothing helped at all. Not even a little change. I couldn't find anything on the internet that sounded like my problem. I just figured I would be like that for the rest of my life. Then, after about a year an a half, I noticed that once in awhile I felt a little better. Slowly I began to get back to normal, and I am so thankful for every breath. I never did find out what it was, but when I saw your post I couldn't believe it because I have never heard anyone describe the exact same thing that I went through. I know this isn't any help, but I want you to know that someone else knows how you feel. I just pray that you will start to feel better like I did. Sorry this is so long.