I don't think that you should regret that decisions. When it comes to a trade and looking at the market value there is always the chance that the market can go either way, and therefore even though you sold at 24k, it is a profit that you have made that you can be grateful for. One of the most important things about trading knows your profit margin that you want to achieve and selling at that point despite possible future assets, because this guarantees you profit rather than going through a much higher risk with waiting and being greedy for more profit. And as you said you learn from this. So don't worry about that.
Great profile picture by the way