After reading bout it, I wish it had been gout. It does explain my joint pain over the years, and the mysterious bouts of swelling in my knees and thumb. This was the worst occurrence yet, and since it was in my big toe, the doctor assumed it was gout.
We got the results back yesterday, and I did some research earlier today. No known cause, and no known cure. At least I know what I'm dealing with, and that's a help.