I think you have identified the main problem, and that is your attention span. I would work on that, meditation is a brilliant method to focus the mind. If you can concentrate on your breathing for minutes at a time, then focusing on more interesting stuff should be a breeze!

Also get some kind of time management software; I recommend Trello, as it is free and uses a great hierarchical system, to organise your tasks and thoughts.

Also accept that, even though you're growth minded, it's ok to suck at something. If you suck at art, it's because you're not drawing everyday, maybe you simply don't have time to do that; or don't want to. I think that is a very important aspect of being growth orientated, simply letting go, and saying; "I'm fine with not being that great at that..." Whatever that, is.

Cg