When your ovulate isn't set in stone at a certain time after your period so it could just be early. I ovulate very late in my cycle so my first scans are always a little off.
Stay positive and wait for the second scan
Hi, I had went through same in last pregnancy, at 7 weeks baby not seen , only empty sac was visible, a week later I had scan again and unfortunately came to know it was blighted ovum, which resembles pregnancy but baby would not have grown or left sac, but try not to worry u should undergo scan again after week or 10 days to confirm that... Good luck...
It could be to early.go back again.i had the same thing happen.my doctor only saw the sac 2 weeks ago and I went back yesterday and saw my baby and saw its heart beating.good luck.