3 months pregnant, feeling insecure.

I've always had a flat belly, I'm 3 months pregnant and my stomach is starting to pop out. It doesn't look like a pregnancy tummy yet, it just looks like I have some extra pounds. I have a wedding to go to today and don't want to wear the dress I got before I found out about my pregnancy because it's tight and you can see my belly. Did anyone here wear tight dresses while you were starting to show? I just need to start feeling comfortable in my 'new' body :(