So, at the doctor's today, I learned a fascinating thing. Apparently, sometimes apparent sinus infections with no apparent cause are actually migraines.
Apparently, they've done a study where they put the appropriate instrument in someone's sinuses, and watched what happened with a migraine. They had all the symptoms of a sinus infection, with no infection, entirely (apparently) caused by the migraine, _and_ migraine meds made it (the symptoms, as well as the migraine) go away.
So now, I get to see what happens with migraine meds next time I have a random sinus infection ('cause migraines run in my family, I've had some, and I definitely have weird apparently sinus symptoms for no apparent reason).
*hunts for a link*
Ah!
Here's oneI note that sinus meds _do_ sometimes help (and almost always more than regular pain meds do), but never fully solve the problem. So! Possible. Still getting checked for allergies, though, just in case.