I'm another who caught COVID at Bluesfest. I didn't even think I had it, just some bug, but was going to get on a plane so went and got a PCR test. My symptoms were: about a day of a slight temperature and feeling a little achy, a few days of a very mild and unbothersome cough that didn't hurt at all, slight fatigue, and minor getting out of breath walking uphill from putting the bins out. No headache, no sore throat. Walked 7km in the hills after a few days of taking it easy and no issue at all. The worst thing was missing the chance to fly to Melbourne and see some old friends at their 50th birthday party (how do I have such old friends when I am so young and vital???)
Interestimgly, I caught it pretty much four months to the day after my booster shot.