Fatigue, joint pain, occasional red rash on face, positive ana (twice), c3 is 73 and c4is 14. could it be lupus?

Probable: The diagnosis of SLE is based on clinical features plus supportive lab evidence. You did not mention how high the ANA titer was and thus a positive one has little meaning. I believe you need to see a rheumatologist given all of your symptoms which may well be from SLE but....

Maybe: The real question is "Should we TREAT you for lupus with godawful high-power medications when you probably don't have it?" People with a clinical picture like yours usually have all this stuff go away after a while. Get seen by a specialty dermatologist for the rash; rosacea can mimic lupus. Ignore low-titer ANA's. Think about getting back to that fitness-focused lifestyle you had as a teen.