Check out "Diagnosing Lupus" in my link below. The Lupus Organization diagnoses based on a "4 of 11" criteria, where only one is a blood test, the others are symptoms. However, some rhuemotologists want to use ONLY blood tests, while others use ONLY symptoms -- the good ones use both.
Keep in mind that a regular doctor is NOT really qualified to diagnosis lupus -- you will want to see a rheumy - and since your mom & sister have illnesses diagnosed/treated by a rheumy, I wouldn't wait, instead proceed directly to the rheumy.
The most important item is to begin treatment for your symptoms -- sometimes the diagnosis comes after the treatment as auto-immune disease is tricky to diagnose!
Hope you feel better soon!
Lynnwood, Lupus & Sjogren's ModeratorDIAGNOSING-LUPUS & LUPUS-RESOURCES
"Life is far too important to be taken seriously" - Oscar Wilde