Alot of times I feel like I can't catch a full, deep, proper breath. It doesn't last all day long, but still happens enough to make me notice. Mmmmmaybe its only my imagination because I am a physically fit person (exercise 5+ times a week) and am fine exercising? I still occasionally get bursts of lightheadedness. Also, today my legs feel weak and jello-like. What could this all be?