You are having Uveitis.
This is an inflammation of the layer of the eye called the uvea, which includes the sclera, the white portion of the eye.
The causes for this are: allergy, infection, autoimmune
, glaucoma, etc.
In your case, your doctor had thought it to be autoimmune due to your rheumatoid arthritis.
Your doctor is probably right and this is likely to be the cause.
Consult your doctor for this. Make an appointment and see him again. This is for two reasons: one is to confirm that it is indeed autoimmune and rule out other causes like glaucoma for example, and the second is because you need steroid drops for this which is not available OTC.
You need a proper diagnosis for this and specially to rule out glaucoma and other causes in the eye itself.
If you cannot get an immediate eye consultation, go to your family physician. Your doctor will be at least do the normal tests and also prescribe steroid drops. This will help you till you get to the eye doctor.
I hope my answer has helped you. Please click on the green 'accept' button below for accepting this answer. Feedback/Bonus will be appreciated. Do not hesitate to ask further questions if you need more info.
Dr. P.Jyoti, MD.