My theory:
Your arms were in sleep paralysis, and you were moving your dream body. The rest of your body wasn't paralyzed, so you couldn't move your dream body.
If you are in this situation again, you should try this:
Gently twitch your body parts that are not paralyzed. You shouldn't be even moving them, just twitch your muscles a liiiitle. Your brain will think that you're in a dream already, and you're moving the body parts that aren't paralyzed. Good luck.

It may be offtopic but I suggest you not to use binaural beats. Instead of putting you to sleep faster, these can keep you awake.