I’m guessing this is not a required demographic question in Canada.
So I was this person, and I didn’t figure it out until later in life.
The trick is, with ADHD, caffeine will slow down your brain but it still speeds up your body (still a stimulant). So too much, and you will be tired and jittery.
Oh it’s already there dude. Anyone autistic/ADHD will be happy to fill you in, I’m sure.