I will be wearing a long dress with a sweep train. I have a bad back and am not very coordinated in heels (and I'm just plain klutzy regardless of my footwear

), so I am contemplating buying white sneakers and just lacing them up with lace or something, to make them a little dressier.
What do people think? Have any of you gotten married in sneakers or know someone who has? I'm a bit nervous about dancing my first dance in sneakers, but I'm more nervous about falling on my way up to the altar!