Regrets? I think that is too strong of a word. I am always analyzing or evaluating what I could do better, what I should have done, what I probably should not have done, etc.
There was a short book I read when I was a kid called Could be Worse. It's a story about a grandfather who had an outrageous adventure. I remember, or at least I thought I remembered that it was a story about his attitude. All these crazy things happened to him, but things could have been worse.
Many years later, I found the book at my sister's house and started to read it to my nieces. It didn't take long to realize that the grandfather made up the whole story! I was pretty upset.
A friend of mine asked me once how things were going. I told her things could be better.
When questioned further about what could be better, as if I was losing sleep over something, I told her that things could always be better.
There was a missionary on my mission that stated his father would rather have him return home in a body bag then full of regrets. I made the mistake of using that word when saying that I had some regrets. The collective gasp was unreal.