Well, yesterday I went to my GP and acquired antibiotics, given that the sore throat's now gone on for three-and-a-half weeks and it's reasonable to suspect it may be a bacterial infection that's moved in on top of the original flu.

Otherwise, it still looks like it's flu, and I am much better than I was, with most of the symptoms (apart from complete exhaustion) being reduced or gone. But yeah, it's taking a long time to go away; yesterday was pretty much the first time I could have made it to the GP's, and it wiped me out for the rest of the day.