Was having a conversation with a colleague about this earlier today.
I've suffered from SP since my early teens. Usually happens when I sleep too much (like when I have a lie in). I get a really high pitched noise like a ray gun in my head, feel a really ominous sinister presence in the room then realise I can breathe but cannot move any part of my body. It terrifies me every time even though I know it passes in a few seconds. My colleague has something similar but she gets a loud clicking, same sinister presence and same paralysis. What are everyone else's experiences with sleep paralysis??