All right, please, please tell me what this means :

I'm in the kitchen and I have one of those mind splitting headaches that feel as if The Rock is body-slamming my brain into my nasal cavity. Groaning, I'm popping two Advil into my mouth and bringing a cup of water to my lips when my sister sways into the room, lowers my arm, peers inside the cup, and, wordlessly, sways back into the living room.

What?