> I would often fall into a spiral of inability to focus -> feeling bad about myself for not completing work that I was generally more than capable of doing -> even less ability to focus. I still have depression, but starting on ADHD medication all-but-removed my most frequent trigger.

I had the same issue!

I told my prescribing doctor this same thing and she trusted me enough to try out Adderall before SSRIs again. Turns out my hypothesis of my depression + anxiety largely being tied to my sense of productivity was right.

After going in for an EKG check-up on orders of the prescribing doctor, I found a fairly benign heart issue that the cardiologist believes may be the cause of my "panic attacks" (eg: my attacks may be heart racing -> panic, not panic -> heart racing!)

All of that from just treating "I feel bad because I get nothing done".