So gestational age is going based off LMP and fetal age is how big the baby is growing, but they add two weeks because they are counting the first two weeks of pregnancy already so if youre 12weeks youre technically only 10 correct? So on an ultrasound the baby should be measuring as a 10 week baby or a 12?

!!!!! EDIT !!!!!

So lmp said i was 10 weeks 5 days but baby measured 10 weeks exactly , would that mean my baby is going to be a big baby because that would mean i “concieved” while on period? And obviously that doesnt happen , plus there was no sex that whole time till about 2 weeks later so i was expecting to be 8 weeks not 10