Your swelling could be edema which would indicate a problem with your kidneys but it also could be an inflammatory process similar to arthritis. Both conditions could be caused by lupus and I had both before my lupus was brought under control. The first thing is to control lupus and then treat any secondary conditions.
Edema would more commonly start in your feet, ankles and lower leg. The kidney condition is called proteinuria where protein is filtered out of blood causing fluids to collect in soft tissue. Treatment is with an ace inhibitor like lisinopril and usually a diurectic like lasix to help get the fluids down. This is normally a very treatable condition.
The inflammatory condition could hit anywhere but is most common in hands, feet, ankles. I had it pretty much everywhere at one point and it was quite painful. It also hit all my joints as well so I was a big bundle of pain. Prednisone treatment eventually stopped it and the pain went away.
See your doctor. Go to your rheumy if your PCP is not experienced in treating AI diseases. If you do have edema you might want to also see a nephrologist about your kidneys.
Hope you feel better,
MCTD (lupus, scleroderma, polymyositis). Diagnosed 2005. Kidney, liver, GI tract, dysphagia, raynauds, Barretts esophagus, quadriplegic in 2005. Recovered and now active in skiing, tai, chi, hiking, golf. Meds: prednisone 2.5mg, imuran 25mg, amlodipine, benazapril, omeprazole, potassium, folic acid, vitamins, maxide and various supplements and vitamins.
Remain optimistic and you can overcome the odds.