I was able to ransack my house looking for drugs, mold and/or other environmental pollutants. I questioned my family members. I ruled out Lupus and Sarcoidosis, also bacterial infection (no fever), and Munchausen's by Proxy. I briefly considered Hypochondria, but thought I'd be much sicker if that were the case.
Here's the white board.

I have diagnosed myself with Fifth Disease. There's not much that can be done; it's a generally mild viral illness that just needs to run its course. Fluids and rest are recommended, and for adults suffering the arthritis symptoms, ibuprofen. "Have adults with joint pain and swelling rest and limit their activities".
Rest. LOL! I would rest, but my husband has gallivanted off to a fancy pants black tie affair tonight, while I was at the elementary school spelling bee. It was very relaxing. Oh wait, I meant not at all relaxing.
Oh well. That'll teach me to not get the antibodies of common childhood diseases.