I have the tendency to keep thinking about things happened in the near (and to a lesser extent, far) past like encounters, conversations or posts. For example, sometimes, someone tells me something I don't consider or understand at the time, but later (after hours at least), because I keep thinking about it, I understand and recognize their intention or what they wanted to say. Usually, I discover that my reply or reaction at the time wasn't appropriate within the context. Also when I write something, like here, I keep thinking about what I wrote, and often discover, but in my mind without going back to the post, and after 2 or 3 hours if I'm lucky to make editing, what I wrote wasn't, for example, consistent, and I need to edit what I wrote to keep my thoughts consistent and not conflicting, which appears to happen a lot due to my lack of concentration (ADHD?). Does anyone experience something similar regarding replaying conversations or posts in your mind over and over again? Is it a form of obsession or anxiety?

I can relate to some of this. Sometimes I will run into a post and reply because I feel concerned about the person because of what they have expressed. I'll think about what they said and how I replied for the rest of the day. I will edit when I think of a better reply or add another post. Other times, after sleeping on it, I will add one more reply the next morning. I do this either to improve upon a faulty first reply or because I think I have thought of an additional helpful thing to say. There is even one person (on this forum), whose posts (just a few of them) seem to sometimes trigger me and I find myself replying to the posts in an overly emotional way which I find quite weird (fortunately, the person is kind and understanding about it.)
PS. Thank you for all of your kind replies to my posts.

[Skeezyks]

Oh yes... all of this happens to me. Some of the things I ruminate about happened many years ago. Sometimes I'll stop & realize that what I'm ruminating about actually occurred nearly half a century ago! But I also find myself re-thinking replies I've written here on PC & deciding that what I wrote was really off-target & wishing I could go back & re-write it. I don't typically try to do so though. This doesn't happen to me with regard to recent conversations though because I so seldom have any...