What to Do?

Ok, here's a new thing for us men. I know that some to most women will read it too and that's fine. It's good to have two sides of something instead of one. But here's an incident that I was approached with. Had one of my boys (partners, best friend, homie, you know what I mean, lol) come to me and he was heated about this past weekend. Evidently, something had went wrong and he was wondering what he did. This is the skinny. Him and his girl somewhat had a weekend planned and in the midst of it all, the planned got changed and he was thinking, "ok since plans got changed, I can do what I need to get done. He turned around and asked her what time was he going home. She kinda flipped on him and was like, are you ready to go? He said that he had some things to do to get ready for the next day. So she gets upset at him cause (according to her) he "all of a sudden" had things to do. Now mind you that she knew what his weekends were like ever since they started talking. Now my question to you is.....Who was wrong, him or her?