Angel, I often have this same problem when I am stressed, or am fearful of an coming panic attack. I have found that a lot of times it is simply a burp that won't come out. When I can get it out the relief is instant, and I feel I can breath again normally. Sometimes this is caused by inflamation, which is caused by acid reflux, which is caused by stress. Many times advil helps for me. Hope this may help you.
