Fights sleeping at night

Ashlie
My five-week-old purposely make him self stay awake all night. you can tell he's tired and he'll fall asleep for a minute or two but he somehow realizes he's asleep and starts flipping out making myself stay awake. he flails his arms and legs around scratches himself, whatever he can do... he doesn't do this during the day time. Why is this happening and how do I stop it.