It's happened to me once, complete with visual hallucinations - this was a couple of years ago. I was fortunate in that I was not alone at the time, and was (eventually) convinced that the experience was not "real".
The visual experience felt horrifyingly real, and it would have likely been much worse had I not been able to conclude that it wasn't real.
The visual experience felt horrifyingly real, and it would have likely been much worse had I not been able to conclude that it wasn't real.