Heart-Breaker

I need to document this so I can look back and read it when Simon is driving me crazy and then I can make myself feel guilty enough that I will stop yelling at him...
The backstory is that Simon has been driving me insane lately--no matter what I say or do, he argues with me and the whining and crying is almost constant. Smadar (his teacher) was just telling me how he's grown up so much and is such a big boy and doesn't cry anymore at gan, etc etc. I guess he is working so hard there that when he gets home, he just lets it all out.
Anyway, as anyone who knows me might be aware, I'm not always so good at keeping it to myself when someone is annoying me and sometimes I may or may not talk to that person in a not so nice tone of voice. Last night, Simon really wanted to play a game on the computer. I told him he could play if he cleaned up the huge mess that he and Eli had made in the living room, building a fort out of all the couch cushions. He said it wasn't fair that Eli didn't have to help (because he had gone to bed already). I agreed with him and volunteered David to help him. Simon was half cleaning and half whining and I yelled at him to stop whining. Then about 2 seconds later, as he was piling up a bunch of toys to bring back into the playroom, I heard David snap at him about something. Simon just burst out with a very frustrated "why are you so angry?? I am doing what you asked me to do!!" David didn't actually hear what he said so didn't respond, but I heard him from the other room and my heart just totally broke into a million tiny pieces. I ran to him and gave him a huge hug and told him that he was doing such a good job and was such a good helper. He just looked at me like I was totally insane.
I let him stay up later than planned to play his video game and then when I told him it was time for bed, he went with not a single word of argument.