Just noticed this post is a couple of months old, so hopefully you’ve been able to talk to a professional regarding diagnosis, if not, then hopefully this advice will help.
I can completely relate! Receiving a diagnosis for me was life changing in many ways. One big one was explaining why I have always been such a loose cannon and why I have always behaved and felt so differently. Why couldn’t I be ‘normal’!
My diagnosis was only recent and I was really afraid of talking to my doctor about it as I was certain I would be told I was being silly. Especially because all of my medical history is mental health related, I was certain he would think ‘oh here we go again 🙄’. I’m so glad I did though. I had to be referred to a psychiatrist to be treated, as GP docs here can’t diagnose and then prescribe stimulants in Australia. Can you get a referral via the public health system? It might take a long time but if you get diagnosed correctly it will be worth it. While you are on the wait list you could put a bit of money away each week and perhaps if you save enough you could get seen more quickly on the private system.
Write down everything you want to explain on a notepad and take it with you. I get nervous and forget all of the important things I want to talk about when I feel like I’m put on the spot. I had 3-4 pages of my ‘proof’; examples of behaviours and traits that are all associated with ADHD and also specific examples.
Do you have any of your school reports cards? My Psych requested to see mine, just to back up her diagnosis as the meds are controlled. I was nervous about this – feeling like a fraud if I couldn’t find any then worried that they wouldn’t have the information she wanted to see. I found one in the end, it was actually rather comical. All the things she was asking me about, the teachers were berating me for in my report! It had ADHD written all over it. If you can dig any up, it will give you some hard evidence to take along with you.
I’ve been honest with my GP and my psych about alcohol abuse, but I didn’t tell them about my drug history as I was worried about being judged and also worried about being denied treatment. I was very similar to you though. Tried most things and partied very hard but never formed an actual dependence on drugs, although in hindsight, it was very borderline.
I hope this helps. If you get knocked back on the public system, save up to see an ADHD specialist, or a Psych with an interest and experience with ADHD. If they have any experience with ADHD, they will recognise it in your history. It will change your life for the better, so go for it, and don’t give up until you find a doc that understands!