Due date wrong?

Caitlin • Wife and a mommy to 2 sons and baby #3 on the way!
So I'm 24w4d and I went to the Dr Wednesday and they told me my.baby was already 2.1 lbs. Which is a pound over what he is suppose to be? Could my due date be wrong? They said they wouldn't change it because it'll be only a couple weeks different. But now idk how far along I actually am!!