Hey there
With my twins my count was over 600 if i can remember correctly at 13 days post tranfer.

With my singlton pg- i didnt suspect i was pg till 21 days post ovulation and my count was 6692
so i guess i am a gal that gets high HCG regardless of one or two- although i was thinking that there was two in there again, but there wasnt

looks like you will have to wait for a scan!

good luck and let us know how you go!
odette