So, despite my mystery ailment rearing its head, I made it to Dragon*Con. Unfortunately, the antibiotic I was on at the time (Levaquin) made me really sick, so I spent a lot of time in my room, sleeping (and one morning in the ER and another in an urgent care clinic, where they took me off Levaquin).
The theory, which is a good one, is that I have a lingering sinus infection (possibly from the cold I got in Berlin) that flares up and gives me nasty post-nasal drip, which gets into my stomach and gives me GERD-like symptoms. While I was taking the z-pak (what I was switched to), I felt better, but in the last few days, my sinuses have felt worse, so I'm going to call my PCP (again) and ask if she thinks I should do another round of antibiotics, because the first one did OK but didn't eradicate the bastards. Persistent cusses.
Anyway, my dear Ben read my story for me in the RFR (because I was sleeping in my room). I made it to things on Sunday, including a great Q&A with James & Oliver Phelps (the Weasley twins), but I was too tired to do much else, and nothing after 10 pm.
I sure hope this whole mess is just from a sinus infection and that another round of antibiotics kills them dead and I never have to deal with this random nausea nonsense again.