I have the same problem and they can't find any problem with my lungs. It isn't panic attacks and they are calling it asthma (although I have never had asthma until I got sick). I have to have breathing treatments unless I am on steroids and since I have been on steroids since February I now breath ok. I can tell when I am late on a dose though.
Try not to panic (although I know that is hard). They will figure out what it is or at least get it under control. Until then, we are here for you