To anyone worrying about there being a problem at their first scan, you should also be prepared that they may tell you you're having twins!!!!
I knew the rough odds of things not going to plan, but I'd never looked up the odds of twins.... had our first scan last week and saw a baby clear as anything straight away, and then as she moved over slightly, I saw another blob which looked similar and she announced it was another baby!!!!!
I have never been so shocked in my life, I couldn't speak! Mega excited about it now though! They're identical, so we will be having scans every 2 weeks to keep a close eye on them!
Good luck to everyone having first scans soon - you never know you could be in for a big surprise! :)