6/7 week very unclear ultrasound

I had an urgent scan yesterday after some spotting and cramping. It was really hard to see much because my bladder was a lot more full than I thought but we saw a sack and a little flicker. She said she was unable to rule out anything like twins because she couldn’t see much due to my bladder. I was happy because I had reassurance that baby was ok and that’s all I needed. BUT, I now have that niggling thought of “twins!?” has anyone had a 6/7 week scan and then gone back a few weeks later to see more than 1🙈😂