YES I’ve finally found some information about this on the Net (even with some graphs 
). Take a look if you’re interested in this stuff:
i think that’s happened to me before, while i’m at school and i’m trying to sleep sometimes, i’ll notice myself having a dream and then i’ll feel all weird and kinda like falling and i’ll like jerk really hard and wake up. what sucks about it is i’m right in the middle of class lol and i have to play it off like i’m just changing positions or something. 
I get this often, it’s about your body fighting against sleep paralysis when your consious isn’t sleeping. When youre still mildly consious while sleep paralysis is coming down at you, your neuralsystem gives a burst of electricity to your muscles thru your nerves to wake them up.
I’ve never “fallen” or been jerked awake but I have experience what I guess could be described as sort of floating. Like the bed beneath me is gone and I’m in mid air but not really falling. Sometimes it even feels like I’m being rotated very slowly, long ways (sometimes with the bed beneathe me rotoating to). If I move(im still awake enough to move my real body) the feeling goes away. But I doubt it is the same thing as falling which seems like a very wild feeling while the floating seems almost serene.