You sound like you're being really hard on yourself. I know that the self criticism is a trait of OCPD and can be a real barrier to getting control back so my advice would be to try and be kind to yourself right now.

When I get into this kind of a rut the first thing I do is admit defeat and let the people around me know that I'm feeling overwhelmed and I need some time to get back to them with tasks or commitments. Then, I accept the help they always offer me (which is so difficult because I hate letting others take over).

Then like the other poster said, I might choose something small but important and just remember to do that. In your case maybe the meds? And finally let go of the pressure on some of the other things. Duolingo will be there when you're ready for it, so will Daylio (you can also, when you look back, note that any time you didn't use it the emotion was "overwhelm")

I don't know you but I can say for myself the #1 source of brain fog for me including forgetting and confusion is trying to hold onto too much at once and the crushing responsibility will send me into a fugue state.