Mistake is defined as an action or judgment that is misguided or wrong.
Experience is defined as practical contact with an observation of facts or events.
As I get old(er) I have stopped regretting my past “mistakes” and now view them as experiences.
It was not a mistake to join the army without getting specific duty assignment or location, (volunteers could get guaranteed one or the other) it lead to the experiences of the following three years. It was not a mistake to not have pursued getting my CPA; it lead me to the Medicare business and consulting. It was not a mistake to have gotten married the first time; these actions gave me a beautiful daughter and a happy second marriage.
I now try to view all actions or judgments, regardless of outcome or results, as being experiences or creating experiences. You should learn from experiences. You should also enjoy them as being a part of life and living. The bad experiences make you appreciate the good ones that much more.