I had an ultrasound done Monday at 6w3d, according to this app, and my last LMP was Nov. 13th but my Dr. has yet to give me my due date because there was only sac and no baby during the ultrasound. She said it's possible I may have ovulated later in my cycle, but wanted to compare my HcG levels. Monday they were at 12,000, I had them checked again yesterday, now I just sit and wait on the call today to see if they have doubled. My last pregnancy ended in miscarriage and it has taken us almost 2 years to get pregnant again. Has anyone else experienced this? I'm trying not to worry but it's very hard.