One other item to consider, if the condition does not resolve after looking at all possibilities, is Lyme.
If you are an outdoor type person and hunt and fish you may have been bitten.
You do not need to be in the woods to get bitten, but even in large cities such as Atlanta, you can get bit from ticks that may have hitched a ride on a pet that was outside.
Even a nymph tick, the size of a pin head, can transmit Lyme.
Joint pain can be one of the symptom of Lyme.
Old wives tail that you need a red "bull's eye" to show you were bitten. BS.
Simple blood test, that you can order yourself, will assist in evaluation.
There are some Lyme post here to look at and a LOT of Lyme support groups everywhere with additional info.