I'm so tired.

I am very tired, but I'm not sure why. I didn't do much today--just class and a meeting. I got things ready for grading finals. I did spend 7 hours on campus though. Hmmm. Oh, and I met with my chair and we figured out how to replace me on 3 committees next year. Yay! But still, that doesn't seem like 7 hours. Maybe all of the student emails and drama were exhausting? Nothing major--just the usual.