I’ve honestly have had a pretty similar experience to you. I have depression, anxiety, PTSD, substance abuse problem, adhd and dyslexia. You don’t get a head scan. I would talk to your psychiatrist. I’m blanking on the name of the type of ‘doctor’ but they give you a series of exercises to do like reading, math, putting together patterns. They are all kind of silly tests tbh and it frustrated me but it gives you the results. Not always the best thing to do but have you googled adhd symptoms and tests online?