Shit. This happened to me last night for the first time. "Woke up" eyes wide-open and was able to look around the room, but couldn't move my body. I didn't see, or hear anything, but felt terrified of something and imminent death- tried to scream, but obviously could not. The whole episode lasted about 5-10 seconds. I'm certain this is God trying to speak to me.
Here's an artist's rendering:
I sleep naked in case anyone was wondering.