I have changed my mind and has a few meltdowns. It can be so stressful making some of the decisions. All I can really say is, when you are going through a mind change just try to be as polite and flexible as possible, but never lose sight of the fact that it is your day! It is okay to change your mind, us women do that a lot, and this is your WEDDING DAY!
Best of luck with the remainder of your planning!