What does this sound like?

I have an issue of ruminating and repetitive thoughts over past things I did that I regret. Just every time I get over one past event or thing I did that I regret, a new one pops up and the cycle repeats itself. It tells me I don’t deserve to be happy anymore and that I am a horrible person because of what I did. 

The events keeping replaying in my head 24/7 and making me feel like I’m a terrible person.

I am diagnosed with ADHD. I’m not sure if I’m perseverating, overthinking, or if I’m dealing with Anxiety.