AFP testing

So my dr said I needed to get the AFP test done. I didn’t think to ask a ton of questions when she gave me the lab order. When I went to the draw today I asked the phlebotomist how much she was drawing because I had seen many contradictions online. Anyways she told me she was drawing two vials so they could test it twice because it was a genetic test and so they could see what was wrong with the baby. But my dr has not said anything about there being anything wrong with the baby.