Brides how did you know that your dress was the One?

I knew my dress was "the one" right away. I had been trying dresses on all day, then there was one that I didn't really care for on the hanger that the sales girl picked for me, but I tried it on anyways. As soon as I came out, my mom's jaw hit the floor, and tears started! When I looked in the mirror I cried also! The sales girl's jaw was on the floor with my mom's....that's how I knew!