Beibei,
Sorry that you are feeling so low at the moment. They did measurements for me too and mine was a day behind in size but heartbeat was about 150bpm. They didnt say much about why the size was behind but when I had the 12wk scan (at 12wk6days) all was well with size and the nuchal fold measurements too.
I hope that makes you feel a little better. Hoping the days fly by for you so you can get that next scan quickly.
Big hugs from me
Sazz