I had my second appointment today.  They did an ultrasound since we didn't see anything on the 1st one they did because it was too early.  By LMP I should be 7 weeks, but I ovulated on day 17 or 18 of my cycle.  baby only measured 6w1d.  She said there is an error of up to 5 days this early and that combined with my late ovulation explained it and not to worry.  I did get to see the hearbeat    She changed my EDD from April 15 to April 21 based on the ultrasound.