Sleep Paralysis

[HoogerBooger]

I have had shit like that once, but it wasn't as severe as your case for sure. Haven't really gotten into that stuff scientifically, but there should be mostly 2 cases how this shit appears: Lucid dreaming - you can move your limbs, but something that appears in the middle of the night usually scares you so shitless that it kind of paralyzes your mind instead of your body. Happened to me once...just felt like something slowly sat beside me on the bed and kept looking straight into my skull when I turned around towards it, but I just couldn't make out what it was, it was all blurry and grey. I wasn't dreaming it or anything. Or was I, fuck knows. When I turned around once again, it was gone. Second scenario should be like Nemesis described, got some buds who have experienced the same kind of shit.