Not so good idea.
Practicing on your bagpipes when you have a sinus infection. I'm not sure if it's a bagpiping urban legend, or if it's actually true, but supposedly if you play GHBP for too long when you're having issues with your sinuses or an ear infection, you can blow out your own eardrums.
All I know, is one round of Crags of Tumbledown Mountain, and I have just about the worst headache I've ever gotten from a set of bagpipes. And this was on my softest, most forgivingest reed. Fortunately, I didn't blow out my eardrums.