Autism

Another "no idea about the situation im CA" comment, but I think this is pretty the same everywhere (in Western countries).

• If you don't think it will help you to know for sure and you don't need others to adopt to your needs and you don't need therapy or even medication, there's no need to go for a diagnosis.
• If you're diagnosed, that's between you and your psychologist/psychiatrist (and maybe your primary care taker and, if you need them to pay for it or further therapy, maybe your health insurance).
• If you decide to go back to school one day, a diagnosis could help a lot with adopting it to your needs. Well, the same should be true about your employment but that doesn't always work out and as you say it could also have negative effects. Not sure if CA has employer protections for cases where disclosing such a diagnosis would lead to negative outcomes.

Personally I suspected I have some ASD symptoms but that I actually have ADHD. But now it's clear I have no ADHD and I will learn later today whether I get clinically diagnosed with ASD. By now it's clear I have some symptoms very strongly, some rather mildly and some probably not at all. Knowing this has already helped me deal with myself better (e.g. less fighting against my nature where I now know they're lost battles anyway) so the formal diagnosis matters less at this point. But it would enable me to get more insurance-paid therapy to start into this "new life" and I could make some demands at work of I feel them necessary (currently that only includes keeping a fixed/own desk when we soon switch to shared desks, but that might change the more I learn about my needs).

In your situation, particularly if you're hesitant about seeing a professional about this, I'd read some books on the matter. I think there are three important categories and I recommend reading at least one of each: 1) scientifically(-inclined) ones that explain the "theory" (like those by Atwood), 2) first-hand experiences (auto-biographies and such) and 3) guidebooks (how to deal with it as an adult or as an employee or such).

Edit: Oh, I forgot one benefit of being formally diagnosed. Or maybe they're two. Autism fairly frequently comes together with other psychological syndromes/whatnot, and a psychologist should be able to identify them which might further help you. Autism also fairly frequently is the cause for other psychological illness and a formal Autism diagnosis might speed up your access to help (and medication), e.g. when you suffer from depression.

Edit: oops, it's ASD in English, fixed