Taryn....
I do have a condition called POTS....but it's nothing like what you've mentioned, and can't find anything even close to referencing what you are talking about. What I have is a heart issue called POTS (Postural Orthostatic Tachycardia Syndrome).
Not sure about the thing w/ your joints. Have you talked to your doctor?
Good luck to you :)
--Tina