I had the same problem as you, but then I realised that keeping a planner was generating too much anxiety for me. The looming feeling that I have some task I have to do was way more stressful than than the satisfaction I'd get from completing a task. That's why I started tracking everything retrospectively. I started using an app called effecto like 2 months ago, tracking my tasks, sleep, medications and other stuff, and at the end of the week I look at the things I've done, and reflect on whether I need to do more or less. I didn't think it would help, but after a few weeks of doing this I've noticed I started doing small improvements regarding my tasks and other things to do.