Tonight, after waking up from a nap on my couch, I experienced a weird sensation. It first occurred when I was still half-asleep, so for all I know i could've dreamed it, but here's what happened. It felt like the back of my head fells asleep, and then for a few scary seconds (5-10), I couldn't move my shoulder, head, or breathe normally, and I felt really dizzy. After the first experience and a few minutes later, I felt another "attack" coming, but I felt that with fight it off by moving around. However, I let myself feel another one, thinking I dreamed the first one, so I'm pretty sure I didn't "trip out" during my dream. If anyone could shed any light on this it'd be great.