After being diagnosed and doing some more thorough research I realized that ADHD had been present my entire life and may also run in my family, it just got much much worse after my accident.
What lazy drs, popular self-help and cheap internet content writing really botch when discussing ADHD is having us focus on the distraction portion and not the underlying reason for why - the portion of the brain responsible for executive function is diminished. This is a neurological problem. Part of the ADHD brain is malfunctioning.
Successfully coping with ADHD is more about learning mechanisms for how to react to stimuli without having the fully developed executive function abilities that others have. But people want to believe they don't have a problem, that they're not disabled. And the disorder doesn't manifest itself very visibly, so it's easy to deny, dismiss or ignore. So they write it off as an environmental problem, something that can be corrected with "proper thinking". This is false. It's a disability, and the solution is coping with the problem.