i'm gonna headbutt ya
a kid who can't sit still yells this when he's about to crash into you like a meatball in a saucepan
"I'm gonna headbutt ya!" he screamed as he ran into the fridge.
"You're gonna get it! I'm gonna headbutt ya!" he yelled while throwing his lunch.
He tripped over his shoelace and shouted, "I'm gonna headbutt ya!" before crashing into the wall.