Measuring behind

Lindsey
I was asked over the weekend to participate in an elective ultrasound for a private ultrasound place ...of course I'm not going to pass up a free scan so we went in....
I am 14wk 4 days (was 14wk 2 days at scan) and the lady said the baby was looking way behind, more 12-13wks....they didn't do any actual measurements, but she said she still saw a yolk sac, which you don't see at 14wks....but the two ultrasounds I've had one at 6wks one at 10wks the baby measured with the October 27th due date
Anyone have any thoughts on this? Or why she'd say I was so far behind? I have my spot tomorrow with my midwife and obviously will ask her just didn't know if this has happened to anyone before, thanks!