And then the rose colored glasses fell off

WC is in his second week of a new after school karate program. He's been picked up at school by his new instructor (who also picks up from other local schools) where they go back to the dojo and have homework/snack time and a 45 min karate lesson or conditioning games.
I thought for sure, with his negative attitude and distaste for change, that he'd have a rough adjustment of it for a week or two. The first Monday, I arrived and he was all smiles. He climbed into the car and his mouth ran 50 miles an hour. Every phrase began with, "Guess what?" And, of course, I had to respond with "What" after every single time.
He loved it...every single bit. I breathed a sigh of relief and then wondered how long that would last. I felt guilty for my pessimism. But, I do know this child very, very well.
How long would his love of this new karate class last... Turns out 9 days.
The building was warm last night when I arrived. Since, it was our first day of temps to hit 70 this year, It was clear to me that they discovered their air conditioning didn't work.
WC emerged from the boys changing room with a frown that dragged the floor. "I didn't have a good day," he declared and dropped to the floor to put his shoes on.
"Because it's hot in here," I asked.
"Because I didn't get a tip," he huffed. (A tip is a piece of colored tape placed on their belt. It signifies they've completed a step towards qualifying to test for the next level belt. They are big deals). He received his first two tips within the first week and I think that set an unrealistic expectation in his brain.
"No one gets tips every class," I countered.
"But, I did my best and I earned it. I can't do better," he argued once we reached the car. "This is why I hated karate."
I tried to explain that if continues to go in and do his best that he will earn the next tip. When he complained that others in the class got tips, I tried to counter with how his karate is all about him and not anyone else. He isn't competing against anyone else. I think he may have looked at my like I was crazy, but I was driving the car and couldn't be sure.
Although, by the time his father got home and I told him that WC had a down day his explanation had changed slightly. He told Jay that Sensei had a long, hard day and was frustrated that afternoon! He didn't even mention the disappointment over the tip.
WC told me in the car this morning that he didn't like karate anymore. I just told him that I loved him and to have a good day.