I think that you can't just backtalk them, because to be honest, assuming you get kids you would get pissed when they talk back, not because they made a good point, but because they don't respect you. You should have been calmer, and maybe explained that "When I wanted to play my own file, she went off of hers, but forgot to save it right then and there. So it didn't have a recent save. When I went on and handed it back, she realized her mistake, and started crying. It wasn't my fault at all, because she forgot, not me."