Oh god dude, dreaming about being eaten alive sounds absolutely awful, the only "pain" I get from dreams is ones that involve drowning. I find that whenever I have dreams where I'm drowning it's usually my body trying to wake up while my mind has already half woken up and then when I finally run out of "air" I wake up legit.
I hate them so much it feels so uncomfortable, it's like wanting to move but not being able to, it's not quite sleep paralysis but it's pretty shit.
Yeah realistic dreams are unsettling as hell though. Ones where the "weirdness" of the dream doesn't seem to be present. Or the transition from dream to waking up is too seamless always trip me out.
The last one I can think of was like years ago when I dreamed about a flash and a giant explosion that rushed through my window, and as it hit me I woke up and I was positioned in such a way that I was looking at the window from nearly the same angle.