I am 25 year old female.I have neurocardiogenic syncope and thryoid problems (low thryroid) which I'm on medications for both. I haven't passed out in a long time nor have I been dizzy. But the past few days I've been extremely dizzy and passed out yesterday morning at work. I felt extremely warm, hands were shaking, and felt like there was a weight on my chest, it was hard to catch my breath. I tried sitting for a while and eating, stinking water, nothing worked. I feel better now but am still dizzy on and off, have a headache, and still having trouble catching my breath. Almost felt like I was having a panic attack, but nothing was stressing me out or scaring me at the time so what could have caused this?