As a 16 year old with adhd taking concerta. Been training for many months now. My question is I'm considering supplementing creatine for weightlifting and bodybuilding purposes. Do you think that there would be a potential reason/risk that should keep me

No. creatine is a natural substance which muscles need to help stimulate their growth. Taking a supplement at an appropriate dose should not pose any problems and certainly not have anyadverse effects with medications. Becoming very fit is very good for ADHD.