Welcome to the Lupus forum. Sorry that you've got something like this going on and you're not feeling well. I have to say, (I'm not a Dr) it sounds like you have some of the lupus symptoms.
Lupus is just so hard to DX it can literally takes years, I'm sorry to say. It took my Doctors 13 years before they said YES I had it and began to treat my condition. Even now they sometimes argue about it, I'm in the rare % that usually tests ANA negative. My other labs are positive and I have 10 of the 11 symptoms. I also have symptoms of other AI diseases too.
I would suggest that you keep a journal listing what symptoms you have. Your pain as to where its located and how bad. I'd write down things like if you eat a certain food and get a reaction over and over again, write it down. Any little thing I'd keep track of it, I'd also try to get in and see another Rheumy and get a second opinion.
Sometimes, we go through several Doctors before getting the right one. Your journal may provide them with a lot of valuable information about what's going on with you.
I've had lupus for 26 years now, lupus patients vary in symptoms, degree of illness, and how they respond to treatment. Some folks are lucky enough it's really mild and hardly affects them. Others are so bad that they may need a kidney transplant (like one of our moderators) or have multiple organ involvement. This is just a really complex disease.
If you think you may have a vitamin deficiency I'd go see your regular and ask them to test you. You're right IF that is what's wrong you should be able to resolve thing fairly easily. However, IF it's Lupus or another AI disease, that may not be the case. There isn't a CURE for lupus, but it can be CONTROLLED. Doctors do not know what causes lupus.
If you have any questions please come and ask we are all more than willing to try to answer them for you. Please let us know how you're doing. Hang in there, it's hard at times but you'll be able to hang on.
DX- RA, Lupus, Fibro, LGL Leukemia, Pulmonary Hypertension, Bells Palsy, Gastroparsis, Blood Clots, Glaucoma, Chronic Pericarditis & Pleurisy, Severe Anemia. Way to many medications to list.