What made angry but now it makes me laugh

The story I am going to talk about happened thirteen years ago. I was at high school by the time and I was the best of my class. It was summer and I was still enjoying my holidays, even though examinations had already started for those who had to pass the course. The day was reaching its end when someone came home looking for me. It was one my classmates asking for a foulder he needed to study for an exam. I lent him my foulder with the promise it would be deliverde in when exams were over. However, exams finished and I never recovered my foulder. Classes begun and I needed that foulder to take a look to my notes for a test, so I asked my partner to give me the foulder back. He told me he would take it to home, so I waited. However, he never went. When I saw him the following day at school I asked againg and witha laugh, he answered he did not have the foulder. Moreover, he told me the foulder did not exist any more because he had broken it into pieces the day he passed his exam. Then, he added with a sardonic gesture that I did not need the notes because I was a nerd. I still remember his face while he talked. The next thing I did was to hit him in the face with all my fury that later my hands ached. After that, I did not talk to him for the rest of the year. Although then we became friends againg, I never lent him anything else, not even a browser.