Well, i also don't support such actions for the bosses to find small small excuses  .... If I know I am right, I never bow my head infront of my boss ! and if it is my fault then i do appologise and ensure him that this will not repeat again which really cools down the situation...

Best time to meet your boss is when he is in good mood and sitting alone specially after working hours. You can meet him and discuss your matter in a professional manner. 

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