There are soo many questions floating around out there in regards to sleep paralysis (SP)
I have experianced this many times myself and have had to work on techniques to induce a lucid dream from that point.
But SP has just happened under no control of my own. I just wake up that way.
Is that so for everyone?

The process in itself is an involuntary action so your body, while in a dream, does not act out the dream. Somtimes overlapping into concious state > SP. That is why I thought SP was involuntary as well.