Thinking about past mistakes is a very bad thing. And this applies not only to cryptocurrency. I never understood it, why regret that it is impossible to return and correct. It is necessary to make conclusions from this situation and move on.
regretting the disappointment of continuing to take care of him will make us worse and won't wake up again, so forget what has happened and take the good side of making it learn so that in the future it can be better.
moving forward also requires experience so the mistake you make is your experience, so you know better what not to do so you don't repeat the second time.