The Use of Inappropriate Volume in Verbal Exchange

I was just asked by our book keeper who answers phones in my office while I go on break if I would like to go on my break now. I didn't want to go on my break because today I hate her and I want her to leave before I go on break so that I can be happy when I come back from that break. So rather than answer politely and have a long conversation about it I simple said in response to her question, at a volume just shy of being a shout, "NOPE". She is leaving right now. When her car pulls out I will go on break. I'm feeling happier already.