My lungs are certainly being shite. My temperature regulation is all over the place: I'll spend an hour felling hot, then two hours later I'm shivering. Random joint pain too, with the Stupid Knee being particularly bad (which combines with dodgy balance to make stairs non-fun). And I keep being overwhelmed by exhaustion and wanting to hide in the dark.
Barakta seems a bit less 'ill' with it, but probably only because her baseline is so awful.
It's not flu, but certainly the worst case of snotty urgh I've had for a long time.