Omega Caveman
When you're so tired that your forehead feels as heavy as a caveman's forehead looks.
David: Yo, bro i got up so early today and I'm definitely feeling omega caveman right now, my forehead is soo heavy.
Buncie: Why did you go back to sleep?
David: My body didn't want to.
Buncie: Why did you go back to sleep?
David: My body didn't want to.