Thought i was 10 but sac measuring 8 weeks and baby only 4.6 mm with no heartbeat. is this a or could i be out with dates? yolk present.

Repeat U/S: It is still to soon to tell exactly how far along you are. Your dates may be wrong. You will need to repeat the U/S in a couple of weeks and repeat you blood HCG levels to make sure they are going up. You need to f/u with your OB on a regular basis to monitor this. However, try not to stress out this will not do you or the baby and good. Good Luck