I do think we overall know ourselves and our health conditions better than anyone else. And it's easy for professionals to misdiagnose due to not being in our heads like we are.
That said.
We autistic people tend to really suck at self evaluation.
edit:
It is worth mentioning that some prefer not to be formally diagnosed due to things like infantilization, not being able to immigrate, being potentially barred from gender transition, etc
_________________
ASD level 1, ADHD-C, most likely have dyscalculia as well. RSD hurts.
RAADs: 104 | ASQ: 30 | CAT-Q: 139 | Aspie Quiz: 116/200 (84% probability of being atypical)
Also diagnosed with: seasonal depression, anxiety, OCD