Yes, I've regretted decisions I've made in the past.

I'd rather learn from my mistakes than regret them

live and learn...no regrets...

Sure, a couple career ones and life ones. I still think I got married too young, but I don't regret it.

I have a few things that I should regret in my lifetime. I try to subscribe to a "no regrets" sort of life. Recently, I had someone point out that this is not actually a healthy way to do things, as regrets are a way to show you how to learn from the mistakes that you make, so I've been trying to try this method of things instead.

I have things I regret in the past, but I don't have regrets anymore.

Of course. I try not to dwell on them, though. I've learned from my mistakes and moved on.