When the little piece of paper comes with the scan that shows the results it's actually a doctor who specializes in radiology that reads the scans then reports them. The sonographer only guesses and takes the necessary pictures. When I had my first scan I was 6 weeks 5 days and the sonographer said it was measuring at 5 weeks 5 days but the final report said 6 weeks 3 days. I wouldn't worry too much about the sonographer and just go by what the report says. Big hugs sweetie xx