I never know how to answer this question. I think of “regret” as being something gnawing; something that haunts you more than it leaves you alone. If that’s the criteria, then I have no regrets.
There are, of course, a bunch of things I wish I’d thought through a little more carefully than I did. I wish I hadn’t invited my biologicals to my wedding. There are a number of incidents where I wish I’d stood up for myself, or stood up for myself more insistently than I did. Of course, I regret every time I ever hurt someone, intentionally or not.
Big picture, though, I think I’m coming up on the plus side of things. I don’t fear karma, and there’s not a whole lot in my past that dogs me. I hope the same is true for you.