Think about how you look at others’ work. You don’t look for every mistake. You look at the scope of the project, the effort required. You consider the time spent on design. You see the form, the choice of wood and think about the time taken to mill the lumber. The hours spent on joining pieces together and the detail in the joinery and the weeks spent on shaping and sanding and how the hardware is hung. You step back and look at the whole piece and you know in your heart how much it took. You congratulate the builder.
Well, do the same to your own self. Congratulate yourself on work well done. Yes do better next time. Always strive to do better, but give yourself a break every now and then. We all make mistakes.