Went to the track this morning and made it one lap. Coughing a lot. Legs thrashed. Obviously still a bit sick, though I did manage to bicycle to work (slow with the kids to President's Circle, then faster up the big hill to my work).
Test results are back. I am negative for tissue transglutaminase antibodies, which means I probably do not have Celiac's disease. This means that no one knows what is wrong. I think I'm going to cry now.