Remember that at this stage 2 weeks difference is less than a millimeter on the scan. So much of the measurements depends on the skill and experience of the person taking the scan. Also remember that measuring to dates is an average and to get an average you need bubs that are above and below that point.

My little bundle has been measuring between 1 and 2 weeks behind from the beginning but we know the date for sure because it was IVF. But everything is perfect - Sunshine is just on the small side of the average.

If you are really concerned ask you Dr for a repeat scan.