Huh. I’ve had the depersonalization feeling, sort of, but it was very different from the SRWOIS. More of an out of body thing, and I didn’t feel afraid about it. Just kind of numb, but not in a bad way. I have smoked pot, but I haven’t felt any depersonalization since then, only before I did, so if THC really does cause it, I’m an exception.
Depersonalization does sound a lot like it. Or, at least, like part of it. One quote from the site which really hit home: “Common objects and familiar situations seem strange, foreign.” This is a bit embarassing to admit, but once it happened and did progress into a panic attack - I ended up directly in the centre of my room so as to be as far away from each wall as possible, because my surroundings were freaking me out.