Those measurements aren't always accurate. I was measured 2 weeks smaller when I was almost due and my baby camw out 9.2lbs haha
They said that through the whole pregnancy I have been measuring weeks bigger. I'm kinda hoping I will measure at 31 weeks bc I'm so ready to have him here
If you usually measure right on track and this is a big change since your last appointment, it's very possible that baby was just in a weird position pushing out your front instead of settling in a neutral position. Generally it's at least two appointments of measuring significantly off before they do any further investigation.
Yes i was all ways 4 weeks Biger but baby was a good size