d say sleep paralysis is very normal and I know some people suffering from it pretty often. If it is a dream like
Jerry, above, asked, then it is not that much of a problem, you can check some sleep-lucid dreaming forums to take control of it- but I don't think it would happen so often if it was.
So maybe if you have a smart phone, or android you can download sleep tracking apps to see if you wake up in the middle of your REM cycle.