Can someone with normal lab results still have lupus or ra or othe autoimmune diseases?

Possibly: About 98-99 percent of people with Lupus have a positive ANA test so it be unlikely to have lupus with a negative ANA blood test. On the other hand, in rheumatoid arthritis, especially in the early phases, a much larger minority of people may have a normal Rheumatoid factor test (but many of those people may have a positive CCP ab test that is seen in RA). Bottom line: possible but unlikely.