my girlfriend and 5 minutes

What does 5 minutes actually mean in a girl' dictionary? When she is getting dressed , 5 minutes means 50 minutes , when she is cooking , 5 minutes means 20 minutes, 5 minutes never meant 5 minutes until today. I was in a meeting when she called me, i told her i'll call her back in 5 minutes .. the meeting dragged on and i couldnt get to her for a half hour. SHE was extremely mad at me. Does anyone have a "situation" to tiem map for girls?