Don't feel bad, happens to all of us. We in daycare just are too hard on ourselves and don't allow ourselves to have 'off' days. Just think, if we were working outside the home we wouldn't think twice about having a bad day, or taking a 'mental health day' every now and then. We are only human and can't always be the perfect happy person that we want to be in our jobs. Everyone has bad days/tired days, we just have to allow ourselves to be human too