Why do i wake up sometimes at night with a feeling of numbness all over my body? i can't shout and move. it makes me weak.

Sleep paralysis: Sleep paralysis is a phenomenon in which people, either when falling asleep or wakening, temporarily experience an inability to move. It is a transition state between wakefulness and rest characterized by complete muscle atonia (muscle weakness). It can occur at sleep onset or upon awakening, it is believed to be a result of disrupted rem sleep.