See your doctor. See your doctor to evaluate the cause. Sle can cause swelling for many reasons including inflammation and renal failure. You need to know the cause so it can be correctly treated.
Rheumatologist. This is definitely a red flag for active lupus, and the swelling can be due to many things. Most concerning is if the lupus is affecting the kidneys, in which case I recommend to go to your rheumatologist asap.