What Causes Numbness All Over The Body?

i have recently been having quick episodes, only a couple seconds, during the day, where my whole body feels like i am going numb or almost like i lose control. the past three nights, i will fall asleep then wake up with my entire body slightly numb, but i can still move. then my feeling comes back within a few seconds after awakening. also i have notice my heart pounding harder throughout the day.