Yes, you could have Lupus without joint pain, it certainly isn't a requirement! There are 11 symptoms for Lupus, generally you mush present with at least 4 of them to be diagnosed. Check out the link below, Diagnosing Lupus. If you are still concerned, make an appointment with a rheumotologist.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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