A whole bunch of things can cause a positive ANA. All it means is that there's some autoimmune problem going on. Mine is always elevated but I don't have lupus, RA or any of that, just an autoimmune clotting disorder. There are whole panels of coagulation tests just for that, but unless you have a history of blood clots (or an immediate family member with a history of them) you don't need it.

Hang in there and try not to worry till you have to.