Hobbling

I went to bed Sunday night feeling just fine. I woke up Monday with my left ankle throbbing a bit, and when I put it on the floor, I was limping like I'd twisted it. Pressing on the inside of the ankle just above the ankle bone hurt. I thought it would go away, but I was on it all day teaching, and it continued to get progressively stiffer and more painful, until I was pretty much hobbling up the stairs to the house when I got home, and grimacing like an old man.

I'm still hobbling around today.

How the hell did I manage to twist my ankle in bed? I sure don't remember doing it...