Definitely not just you, I get this sometimes too, and it makes me snappy and short tempered until I can get away. It comes on all of a sudden, like I literally just snap. I have anxiety issues too, from what others have said, that seems to be a common theme. People trying to talk over loud music, being touched or talked to while I'm in pain or tired seem to set me off, but just being too hot, hungry or thirsty seem to be my personal triggers, then it takes an environmental trigger like too much noise to set me off... I absolutely cannot handle people talking over each other-people have even commented that I look physically uncomfortable when this happens, like I'm in pain!

Not pleasant, I haven't tried sitting in a darkened room, and I haven't ever been able to put a name to it, I tell my partner I feel like I may be overstimulated, that's the only word I've been able to put to it.