Also: Lupus and Pso/PsA actually have a lot of symptom overlap (and all of that could be PsA, but overlap syndromes (having two or more autoimmune conditions) is unfortunately a fairly common phenomena. An ANA (blood) test would give you a pretty good idea... there's a couple other antibodies too. But it's also totally possible that it's PsA that's mimicking Lupus (RA and IBD can also be mimics). My rheumatologist tested me for Lupus too because I get the butterfly rash on my face, but it doesn't seem to be caused by sun exposure (it's actually kinda random?). Also the blood tests were negative (we were just chasing antibiodies that weren't there, fairly certain it's all Psoriatic for me). It took about a year before we figured out that I had PsA (after 10 years of misdiagnosed palmoplantar Pso).