Parents of ASD kids - diagnosed after their kids?

Hi

My younger son has just been diagnosed with ASD at the age of 13. My eldest is 18 and awaiting assessment. We'd always felt they might be but till fairly recently school and health staff didn't agree with this. I was stunned when son's diagnosis was actually confirmed as I expected to be told I was making it up. 

I've a fair bit of knowledge of autism as my brother-in-law is autistic and a lot of my husband's family have a lot of autistic traits but aren't diagnosed. However, I didn't really know much about women on the spectrum till now. The more I read, the more I feel like it fits for me in a lot of ways and would help explain why I've struggled a lot in life. I think other parents have had this feeling after their child's diagnosis but I don't know whether to just leave it (I'm late 40s so not exactly young) or to take it further. 

Would love to hear people thoughts if they've been through similar.