Our cats do this every morning the minute they know we are awake while still under the comforter. They are letting you know that they want to be feed !!!!!
Mine does it because he wants to play.....at 4 am!!!
I woke up sometime last night in the middle of the night with him next to me, staring me in the face, and the minute I cracked my eyelids he started the digging LOL I shut my eyes and ignored him and went back to sleep, thankfully he didn't start the pouncing game!