Good luck OP.
I was recently diagnosed at 53 and it was a bit of a surprise. It has been interesting learning about how my brain works and I'm still basically thinking through thousands of examples of past decisions and behaviour that I see now in a new light.
Having said that, apart from having this fact of the diagnosis in my mind, not much has changed. Knowing I have it hasn't changed my behaviour. It will take time and effort, maybe coaching or therapy, a lot of self work for sure.
My point is that the diagnosis itself doesn't matter all that much. If you think you have it then approach the next steps assuming that. There's so much stuff available online, it's crazy. Articles, Facebook groups, forums, podcasts, coaches etc etc. It's yours for the taking. Loads of support out there.
What you won't get without a diagnosis is a prescription. But I've tried medication and cannot physically tolerate it. That has been disappointing but then again...it wouldn't have really changed me. I still have to learn new skills and tactics to make my life easier and better because the meds made me able to focus better for a few hours but not necessarily on work. I'd get stuck in a trance looking stuff up on my phone.
Anyway I'm rambling a bit. But don't be nervous about it OP, whatever happens you can still get help.