Hi Tink,
I know this is a very frustrating situation to be in. Took me about 7 years of symptoms, blood tests and good doctors to get a diagnosis.
Other blood work they'll look at is you ANA, ESR, CBC, liver function tests, kidney function, Compliment levels. There's probably more I haven't remembered.
They also rely heavily on symptoms. If you're presenting minor symptoms with no skin rashes, it will take a long time to figure it all out. As symptoms increase, they'll pay more attention.
You are being treated with medications right? Who's telling you you don't have lupus? If you're getting the runaround you should consider getting new doctors. You've probably been through a bunch already! I went through 3 rheumies before I got someone to take me seriously. I hope you can find some reassurance soon.
Ginny