No Idea What This Is, and it's Freaking Me Out!

[LuciferSam]

Every so often, I will wake up in the middle of the night with the weirdest physical sensations: sometimes it feels like someone is shoving a thin pole like a broom stick into the centre of my back and making me arch forward, and I can actually feel a localized centre of pressure like a small circle, exactly how I would think the end of a broomstick would feel. Other times I feel like somebody is sitting on my crotch, again, with the pressure focused in one distinct area.

I am fully conscious during these, and I am aware enough to tell that no person is there just screwing around with me. What could this be?

[Sir Suomi]

It's possible that one of your nerves have become pinched, and in that case, you may want to see a doctor if it persists. Do some research first, though, because that was only a guess.