If that "long story" is stimulant abuse, the shadow people are much more pronounced than in regular sleep deprivation. So is the psychosis.

I also had a few years period where I would get constant sleep paralysis during sleep. Multiple times weekly. It's a very unique feeling and you know it when it starts coming on. I trained myself to ignore it as best as possible and "go back to sleep" instead of opening my eyes. Much harder when it's incorporated into an actual dream though instead of just seeing/feeling/hearing things in your room.

After doing that for a while, I had an extremely intense episode where a vortex/black hole was at the bottom of my bed sucking me into it, and I just KNEW if I didnt fight it that I'd be dead. So I fought for my life. That was my last episode of sleep paralysis... going on 5 years now.