I Have Sleep Paralysis

sometimes i wake up right after falling asleep and my whole body is tight and cramped like im flexing every muscle in my body, my jaw is shut tight, so tight it hurts, i cannot move it without fear of breaking my teeth. when this happens i close my eyes and think about something else and fall back asleep. its a weird feeling, maybe il try for an obe next time it happens

It is caused by your brain chemically paralysing your body for natural non fidgeting sleep
If you awake before your brain dissapates the chemical,,you experience this.

It's normal. It just means that your mind is conscious while your body is asleep...

Occasionally yes. It is quite natural although frightening.

I've experienced it. I once heard growling.