A lot of ADHD symptoms can also mimic other disorders like PTSD, depression, bipolar, etc. that's why sometimes professional help can also help with determining/confirming the condition - not just necessarily for the purpose of getting medications. I personally don't like to experiment with stuff since I don't want to risk spending money on things that may not work for me (same with skincare lol) but whatever works for you!
Same with me with hyperfixation. To the point that that's the only thing I think about on that given time. Then you invest time and money for the new found hobby but then you lose interest and you feel guilty for spending so much.
We are opposite with caffeine effects. Caffeine makes me sleepy! 😂 Do you think you are hyperactive in that case? I think it's the hyperactive ones who can get more active with caffeine.
It's so hard to make a structure for ourselves when our whole life we've been taught to function like neurotypicals.