Gwen

I really don`t think you can tell by your HCG levels if your carrying twins as this pregnancy I conceived twins and @ 24DPO my HCG levels were 600, which was extremely low for a singleton pregnancy let alone twins, but alas I was pregnant with twins, I did loose one of my babies 2 weeks later.

So after my levels being so low in a twin pregnancy I truly believe the only way you can tell is via an u/s.