Most doctors will not give a definitive diagnosis until all tests have been run and results have bee considered. As Teriod mentioned, Lupus never affects any of us the same way. Doctors will consider test results in conjunction with symptoms your daughter might be presenting.
Unfortunately, for many of us, it took months to a year before we finally were diagnosed. If you go to "Newly Diagnosed" in this forum, you will find a post that outlines all of the tests and criteria necessary in order for a Lupus diagnosis to be made.
I agree with you and Teriod, keep copious notes on your daughter's symptoms and her reactions to things (such as food items, sun exposure etc.) and take them with you when you see her doctor. Is she seeing a rheumatologist? If not, request that she be seen by one or at least someone who has knowledge of Lupus (and/or autoimmune disorders). I wish you the very best!
Peace and Blessings
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