You can't ever anticipate how other people will react, but today that is especially true. There is a high probability that someone, at some time, will overreact -- including you. But you shouldn't try to modify your behavior in order to avoid it, because you will only end up stressing yourself out. Just carry on as today you normally would and deal with any emotional outbursts as they come. And if you're the one who blows your cool, just make sure you are quick with the damage control.