Thanks to those who left such nice supportive thoughts and comments. I decided to leave the comments private in this particular case, but I really do appreciate your kind words.
I ran my first track workout in a long, looong time last night and I immediately came out the other end with a head cold. It doesn't seem logical that I could catch a chill and get sick quite that fast just from running four miles on a windy track, but causal or not, that's what it feels like happened.
It was a fairly low intensity outing, which seems sensible at this point:
2 400s: 1:30 each
1 800: 3:05
1 mile: 6:30 (felt faster!)
1 800: 3:07
2 400s: 1:32 each
Plus a half mile warm up and cool down. Surely that shouldn't have made me sick, but I haven't been sleeping nearly enough of late, so perhaps my body just didn't need much of an excuse right now. Ah-choo!