I found your experience resonated with me. There are common elements although I believe I am much older than you (65).

The main advantage of a diagnosis, official or DIY, is that it gives you a framework to evaluate the actions of others within. You can go back and look at episodes in your past from the perspective of being autistic.

Because, even if you didn't see it, the people around you did. When you rethink your past, knowing that will make things much more understandable.