Hi Nic,

Don't stress about the size thing and if you aren't happy with what they sold you you are entitled to your money back. Ring them first and ask if they could order you a 12B and explain that you aren't happy with the one they sold you.

Then when you go to see them they should have your preferred size and you can try it on and compare. Otherwise I think you are supposed to swell lots just before you give birth and just after when your milk comes in, so chances are you will still get bigger. I haven't been pregnant before so I can't confirm this - perhaps other mothers could?

Hope that helps!