I'm not sure what med would help the most for obsessive worrying, but I used to overthink things a lot, a long time ago, which is the same or similiar, and I had to teach myself to stop overthinking/worrying. I wrote stop on an index card and hung it in my work area, and whenever I started overthinking I would look at the index card and stop myself.

This probably sounds silly, but it really worked! I was the worse overthinking worrier ever, until I taught myself to stop, and now I don't do it very much, if really at all.

Just an idea.

Hope you find something that helps!