Odd shaped gestational sac?

I had an ultrasound at 6w3d, and at first the tech found what looked almost like 2 sacs. Picture two, separate, almost round sacs with a SUPER thin line connecting them. Like so thin you're not even sure it's there. She thought it was empty at first but then saw baby squished right into the beginning of the connection. She did detect a heartbeat. She went to grab a doc to confirm what she was seeing, but they were in surgeries/with patients. What she came back about 10 minutes later, she scanned again, and the sac was a normal, round shape, baby and yolk sac were very clear, and we could see the heartbeat. She said it could have been a uterine contraction, and my bladder starting to fill up in the waiting time. Everything seemed normal! When I did see the doctor, he said so far so good, but to mention the odd shape when I come back for another scan in 2 weeks. Has anyone ever experienced something like this?