What does it mean when you wake up and your bed is rocking back and forth very lightly almost so lightly you don't know for sure if it's your mind or not. Also what else do you do when your asleep or falling asleep then suddenly your bed moves like someone sat down on it and you wake up?
But yes, demons exist. (Although the term is often misunderstood)
Maybe it was just an earthquake, maybe you were overtired?
Might have even been a ghost, who knows.
I wouldn't worry about shaking beds, you're fine.
Sometimes If in my dream I trip or fall or throw a punch I might do it in real life and wake up scared.
OR yeah an earthquake. If someone touches you in a dream you might feel their lingering touch when you are awake.