How do you know if you have lupus?

See a Rheumatologist. If you suspect you might have lupus see a rheumatologist. Diagnosis is based on symptoms, history, physical exam and laboratory tests. The earlier you get diagnosed the sooner you can get the proper treatment.
Complicated. Lupus is a difficult diagnosis to make. It would be hard to diagnose yourself with lupus. It may be best to see a rheumatologist if you are concerned about this diagnosis.