has anyone been pregnant with twins and they missed it at the first ultrasound?

Since I found out I was pregnant I just had a gut feeling I was carrying twins. My husband has a lot of sets of twins on his side of the family. Well when I went to my first ultrasound at 7weeks 3 days the lady was rushing me out, barley even letting me hear the heartbeat. Horrible experience. Well I'm now 11weeks 1 day. And I listen to my baby's heartbeat on my home Doppler every day. Well for the past 3 days I think I have been hearing 2 baby's and my heart beat. I know it sounds crazy. But any thoughts on this?