I'm going to pop in an answercI made to a previous thread that seems applicable here as well.
From what I've seen, those with a later diagnosis are more likely to fall in the camp where the diagnosis / identification comes as a relief, whereas those who receive a diagnosis (or self-identify) up to early adulthood (say 25-ish) are more likely to have concerns.
This is likely because the former often already have a lot of life experience and quite often have already developed some sense of self, and so it's easier to learn something about yourself, reflect on how it impacted your past, and then look ahead on how you can use this knowledge to adapt to things going forward.
As a teenager or young adult (as your profile suggests), you're quite likely still very much in the process of finding yourself, maybe still deciding on what you want to do your post-secondary studies or training in. To know you're different can mean getting help and avoiding some of the pitfalls that some of us later diagnosed have fallen into. But at the same time, knowledge, and fear of the unknown can be overwhelming.
Sorry if I'm not making much sense. I'm kind of tired but I did want to respond with some thoughts.