I just got back some lab work that shows I have low blood carbon dioxide, aka hypocapnia. Anybody else? Is it a symptom of OI or POTS? I think it might explain a new symptom, in the last 6 mos or so, that reminds me of years ago when I spent a few nights in a mountain climbers' hut halfway up a mountain in Ecuador, and would wake gasping periodically throughout the night. The same thing seems to be happening. It's not really anxiety, I mean it doesn't have the emotion of anxiety, just the physical jolt. Also heart palpitations every once in a while. And a feeling I'd describe like my heart turns to jelly. Familiar to anyone?