Jagged gestational sac

[maia123]

I don't know if anyone can help .. I've been so worried recently, so im supposed to be around 8 weeks pregnant and I've had a few early scans (internally) , I had one 2 weeks ago and they found the yolk sac inside the gestational sac that had doubled in size since my last scan, then I had another scan today as they want to see a fetal pole, they found one measuring 3mm. Which is too small to be 8 weeks pregnant, so I'm going back in 2 weeks. But clearly something is growing?? They also said my gestational sac is a bit jagged, which I'm worried about too, has anyone had anything like this before and how did it all go? I'm so worried :(
Thankyou!!