I Have Had Sleep Paralysis

I have instances of sleep paralysis, frequently with hypnogogic hallucinations (you can't move but you see and hear things around you). The scariest one was when a black, humanoid shape with huge hands emerged from the wall beside my bed. It put one hand on my chest and the other over my face. I could feel myself being pressed in to the bed and I couldn't breathe. I fought to move until finally I gained enough control to move my arm, and as soon as I did it disappeared. The strange thing is that there is no sensation of waking up, and the memory doesn't fade like a dream. I slept with the light on for days after that.