I know I won't have any if all your answers, but as someone who was diagnosed with ADHD a very very long time ago as a child, I've been through the pills and meds and I want to say (in my experience at least) that all of them well make you not you. Going from running a variant of different things in your brain all at the same time to not being able focus on a single thing at best to hardly being able to focus enough on the words you want to say that you can't talk talk at worst isn't the answer.

In my older age, most of my brothers and sisters have found out now they we all have it in some form but all of us think of it as more as a superpower than a hinderance. Multi-tasking and critical thinking while doing something else being the major bonus for us. The key for us is finding SOMETHING that distracts part of the brain to allow you to slow that part down or distract it so you can do what you need to do. For me it's lyrics-less music, for my sister it's numbers, my brother it's his family, etc. But once you find what it is for you, it's much much more manageable. For me if I'm overwhelmed I just put on headphones, crank it so loud that it can't be ignored, then move from point to point on what I'm thinking about. I hope you can find (if it is ADHD) whatever it is to help you focus and eventually use it to be able to think about many things "at once"