How common is it to ovulated later than expected? I had an ultrasound today and I thought I was 6 weeks 1 day and ended up only measuring 5 weeks 4 days (so three days off). They were only able to see the gestational sack and the yolk sack, which they said was what they would expect at 5 weeks 4 days. I am kind of freaking out. Has this happened to anyone else? Praying that this baby is okay!