mom’s how does this sound?

I went to the doctor Sept 4th for my first ultrasound baby was measuring 12w3d but based off my lmp i was like 11 weeks so I had a follow up yesterday Sept 17th and the lady said he measured 13w5days so he only grew a week? I’m so confused but the heart rate was good and the only difference is the first one was transvag and this one was abdominal. She seem like she kinda rushed too but that’s weird to me idk