I used to get this when I was a kid. Scared the hell out of me, it's the looking right into your face thing that I hated, as the two things that came to me were not easy on the eye. Anyway, as time went on I was able to keep them away until they faded altogether and looking back, now as an adult, I tried to put it down to sleep paralysis, but now I'm not so sure. Anyway, you don't seem too scared by this, so good on, there's no reason to be.