Femur and abdomen measuring small

I am 38 weeks tomorrow and had an ultrasound today due to baby being breech... they estimated a weight at 6lb11oz and the tech mentioned babys femur and abdomen are measuring behind........ I am

Not sure what that means and now I am stressing about it.. the dr came in to talk to me and didn’t say a word about it? Has anyone experienced it and every thing been fine???