problem today at my tutoring job involving an angry father. advice?

[Dart1]

I work at a tutoring center and I had this new student. Our first session was fine. He came in with homework and a study guide his teacher had given him. He came in on Tuesday with nothing to work on so I tried to review on different stuff that we had done last time. he continually tried to just draw. at the very end of the session he asked if I could draw and I said a little. i drew a little doodle. he took it home and told his dad that we spent "half the time" drawing and that wasn't true. so today i got fed to the wolves. His father was waiting at the place when I got there and he jumped on me and said i aint paying you for art encouragement. He really let me have it, insulting my degree, insulting my ability as a tutor and as a mentor. This father had no idea what happened in that room other than what his son told him. The kid came in with NOTHING to work on and wanted to do nothing but draw and talk about sports. I tried to get him back on math over and over in an effort to help him. I am sensitive. I can't help it. This is eating me alive, I feel like I got jumped on by an over reacting father and a doctor at that. I can't sleep tonight because all I see is this guy's face in mine telling me how bad of a person, tutor, and mentor I am when his kid showed up to tutoring unprepared. I tried to review what we had done in previous sessions and he would pay attention for a few minutes and then he just wanted to draw and talk about anything other than school work. I am not a baby sitter. Please anyone tell me how to forget this. Tell me how to put this behind me and not think of it because its eating me up inside. It really is, this creep of a father yelled at me and I feel like he should have gone to the administraters and not to me. Please someone how do you forget something like this? How can I forget and put behind me all the things he said and for the love of peat how do I forget this snarling face right in mine? I am 26 year old adult with a bachelor's degree and pay my own bills. This father treated me like I was garbage and I am extremely angry about the whole matter.