Gestational age and new due date


So I had my NT Scan on Monday when I was 12w2d. Baby was measuring at 13 weeks and my due date has now changed from 27 Jan to 22 Jan. Does this mean I say I am now 13 weeks along when asked?? I updated my due date on this app and of course its showing me as further along. Just unsure if I should go along with it when discussing my pregnancy?