>>16739720It's similar to those times you've been really focused on something, like maybe a new game you're hooked on or in a tense game of CSGO. Heart's beating faster, hotter, more attentive, you'll talk faster and say more, hands will be a bit shakier etc.
Take too much and the above becomes too intense for therapeutic use; you'll be a bit manic. A proper dose should feel calming despite it being a stimulant. I personally don't believe I have ADHD, but I really burned myself out, so low dose amphetamines give me the energy and focus needed to keep going.