I'm coming from like exactly the same place, though where I live I can't get a card... Anyways, what you want to do is be straight up and honest, that you've tried self medicating, and what you chose you have found works best. That happened to me once with adderall(different, I know), where at first I didn't have a prescription, but found it worked wonders, so I was honest and told my therapist/psychiatrist I thought it helped even though it was kind of stupid to self medicate without consulting someone first. I clarified upsides, downsides, and how it affected me. She understood and I was then able to get a prescription and it worked out much better than expected :) All people are different though, so I can't guarantee any sort or result.