Good on you for investigating this!
Naturally, the screener test is not the same as a diagnosis, but it is an initial level of understanding - congratulations for achieving that.
I can't advise you on America- specific matters like cost, Medicare, and whether there is any reason not to see your main doctor.
Personally, I think this is a great thing to be aware of, and I like to be open with it, whenever that can help someone treat me better and more effectively.
Consider finding and using a psychologist with expertise in Autism in mature adults, because some of the generalists lack a lot of knowledge that they would need to give you a good outcome.
Good luck.