Throwing away belonging - did I go too far?

So I think I made a bad parenting call last night. My 4YO son was being disciplined for misbehaving at school by having his Kindle taken away for the evening. That's standard, but while he was in his room, he opened up his backpack and his sister's backpack and ripped up all of their worksheets and the pictures they had colored. When I saw what he had done, I was furious. I wanted to add an immediate punishment rather than just extending his current punishment by a night. I noticed that there were clothes and toys all over the floor, and made a snap decision that because he destroyed something that belonged to someone else, he should understand how that feels. So I threw out his favorite baseball cap, then had him throw out all the pictures he tore up. He was upset for about a minute but then seemed to get over it.I still haven't gotten over it. I wanted to save those pictures because they were from their very first day of Pre-K. I was very hurt and acted on an impulse instead of taking the time to let emotions settle. I wanted to teach him empathy, but I worry that this could genuinely hurt him instead of learning from the experience.I've thought about letting him go in and get the hat out, but I don't want to send the message that punishments aren't going to be followed through on. I was leaning towards letting him earn a new one for a week of good behavior at school. What would you do? Do you think I've caused a major problem? via /r/Parenting https://ift.tt/30xCtuu