As my friend said, "I'm not perfect, neither are you." No one is going to do everything exactly right all the time. In fact, none of the time. You and everyone else WILL make mistakes. Not oned dancer can tell you they have never ever messed up, either while learning a rouitne or even just practicing by yourself. About having a bad day, it happens to everyone. Like Laura said..they might have just had a bad day and every little thing was bugging them. Dont let them get to you! Keep dancing and remember that you are not perfect and you will make mistakes, but so does everyone else!