Sometimes when I'm just about to drift off to sleep...?

The same Thing happens to me... EVERYNIGHT!!! And I be wanting to jump up and look to see what the heck be shaking my bed, but I dont! It happens the same way, I would be drifting off to sleep then, my bed starts to feel like its shaking... But Then I notice that my heart is beating at the same pulse the bed is shaking... So It might be your heart making you feel likes your bed it shaking... Cuz I promise the same thing happens to me.