I think I figured out why today. I didn't eat dinner last night.
Well, I didn't eat a good dinner. What I had for dinner last night and the night before was half a jar of Pedroia premium salsa with black beans and corn and half a bag of corn chips. Not exactly the fuel of champions.
So here's what I'm going to do. I'm going to make myself a berrylicious smoothie of awesomeness, go to my weigh in and try again later. Perhaps just a long, pleasant walk along the river or something and then map out my workouts for the week. That should fix the problem for today and (hopefully) going forward.