Measurements? Due date?

Natasha • 21, A happy wife, and a proud mommy to Josiah! Life is sweet, and I always try to stay positive! 🌞
Hey everyone i'm 28 weeks due in Sept.12th , I just left the doctor and he said i'm measuring 31 weeks.He said if the baby gets bigger then we will do another ultrasound. Does this mean my due date can change??