Sore throat blues

I got a flu shot this year (for the first time ever, only because they happened to be conveniently offering at the mall when I was in Atlanta), but nevertheless feel achey and sore-throaty today, and our final concert is this afternoon. It's been coming on for a few days (I coughed through our first concert on Friday), but seems to have settled in today. I have no time to be sick. At least I am not playing flute, which would be hard on a sore throat.