Yeah, that first part happens when you on occasion mentally wake up faster than your body does, which is then still sleep paralysed. It can be pretty scary the first time, as it feels as if there are shapes (ie. humanoids) lurking around you. Also when you try to move your brain remembers and plays the motion as if it's happening, but you're still paralysed so you keep resetting back to whatever position you're lying it. The same probably holds true for sight.