Yeah, I need to relearn how to breathe. I think I've been a shallow breather all my life. Probably part of why I'm so quiet too. I just talk from my chest. I never give my diaphragm any exercise, so it's no wonder I have difficulties when I do have to use it when performing and such. I'm always out of breath. I've been having pain in my chest too, which I'm thinking may be caused by taking a short, gasping breath when I feel like I'm not getting enough air. I think the anxiety is a contributing factor, but it's probably also just bad breathing habits.
Interestingly enough, as I'm posting this right now I can breathe just fine. There's no tightness in my chest or anything. Not sure that I'm doing anything different. I've been just sitting here before and still have had problems. It's weird how it comes and goes.