So today I had to have a follow up scan due to bleeding last wk..going off my lmp which was the 13th jan...and I know I ovulated 16days later as I charted...I should be 7wks 1day yet the tech measured me at 6wks 2days?!?! How is that possible? My scan last wk showed 2 sacs yet today there was only the 1 with a heartbeat. This is my 3rd pregnancy so u would think I would have some idea by now but clearly not haha. Can any1 help with my confusion please