I'm sorry, I might not be of much help since I don't have ADHD, but is it okay to know a bit how you arre working? Are you focusing on one thing then do something else when the first thing is done? If yes, maybe switching often between your different tasks may help. And, just take breaks when you feel like you can't focus anymore x)
Also, is it difficult for you to work alone? Maybe working with someone else might help too? I don't know, everyone is different, so I'm not sure about this one advice ^^"
I know that I personally prefer working alone for my own project(s), because I don't have much good experiences doing it with a team. There is pros like learning new things and interacting with new people, but there is cons that can bump you too (eg: team members vanishing without a word, others being demotivated, things like that). So yup, in fact, I think what I'm saying doesn't help at all... Sorry ;-;
So at least, I can wish you good luck! I put your game in my Collection, because I really like what I saw from the screeshots and I'm weak for games with cute graphics like yours! (>__<)
You can do it! <3