Can you just straight up ask for a referral to a psychiatrist? If you specify there's something you want to be evaluated for (ADHD), and you have specific reasons why you think so (checklists can help), and you have specific examples of how it's impaired you in important ways in your life, then that should hopefully be sufficient for any reasonable GP in our country. CADDAC may have some useful resources you could use too (e.g. checklists and info on standards for ADHD treatment in Canada). But the sooner the better. I don't know how it is in PEI but where I am, I had to wait a couple of months. It's a shame mental health is so low a priority in our health care system.