Wedding Dress

help!

I'm going dress shopping tomorrow and should have something in hand, hopefully. Here's the thing though....I just found out I'm pregnant!!! It should only be a by just a few weeks though. William and I actually got legally married on February 4th, for various reasons, basically we're trying to get FULL custody of his daughter ON PAPER and we thought it would give us better chances if we went ahead and got married. He and his daughter's mom were not married. It's a loooong story. Doing all the math, I'm pretty sure conception happened on our "wedding night".

So now, I'm worried about dress options. Will I be showing yet? Will I put some weight? I don't know what to do! I'm thinking getting a bigger sized dress and then getting last minute alterations. My bestie suggests sticking with a corset back at the least.

Any advice will be most helpful!