Is it possible to have Lupus, but still have normal lab results?

Hello. For awhile now I have been expieriencing symptoms that almost match the symptoms of Lupus. I am 15 years old. My doctor did the lab work, and everything came back pretty unremarkable, although he thinks that Lupus is still a stong possibility. He is sending me to see a rhuematologist tomorow, to further evaluate me. Is it possible to have Lupus, but have it not show up in lab work? Any info is appreciated. Thanks!