hey @Staceace111! Great questions!
When I first started my anti-depressant, I tried two different low doses. When I felt like they could be more impactful, I asked to go up a little bit again. But the higher dose made me feel kinda yuck (too brain foggy, not myself). I definitely felt better on a lower dose. I'm currently tapering off completely after a number of years. Me weaning off was not because of anything wrong with the medication or how I was feeling, more about feeling like that medication has served it purpose. So, with my GP and Psychiatrist, I've been tapering down for a while.
For my ADHD medication, I tried a few different doses and have slowly gone up until I hit a dose which really felt right.
I don't know why sometimes different doses feel better. I think everyone is different and working with a GP or psychiatrist is definitely how to make sure meds have the best impact.
Is this something you've been experiencing @Staceace111?