Baby measuring a week ahead! New due date


Today I was supposed to be 12 weeks 6 days and ultrasound said 13 weeks 6 days! I'm so confused because just last week (8/9) I had a ultrasound and it said 12 weeks and 1 day.

Baby grew that much in a week or some ultrasound tech got it wrong?

Happen to anyone else? Also what do you guess the gender is!?