For me, there are two different examples. With one, I suddenly feel the need to increase my rate of breathing, and for no obvious reason. I realize that It's more than I should be doing, but if I try to slow down I feel a little panic. With the other example, I find it impossible to take full breaths, in that I can't fully exhale. If I do, it sometimes causes palpitations. Is this the bloated feeling you refer to?