Diagnosis?

I think I might be on the autism spectrum. I started speaking in full sentences at a year old, and could read fluently at age 2. I had selective mutism, refusing to speak to anyone except my immediate family, until about age 5. I think part of it may have been because of my mother, who is extremely socially awkward, which gave me the impression that socializing in the outside world was unsafe. I was obsessed with dinosaurs and knew everything about them. I would often get focused on one thing, such as reading a book, and not notice anything in the outside world. I had a best friend that I used to play with, engaging in parallel play and never speaking to each other. I always had difficulty making friends. I remember in school that I knew all the words, but felt that I was missing something because whenever I spoke, the timing seemed to be off. I dealt with it by staying quiet and watching everyone else. I never had a problem with eye contact, except that people would get mad at me for staring. I did have friends in the neighborhood, and my siblings and I played outside with them nearly every day. I did very well in school, getting A's on all my tests, but never could remember to do my homework. I passed the test to get into the grammar school, but I didn't fit in with the other students and was socially ostracized. Then my family moved, and at the next school, I found my social outlet through sports, where the rules are clear and talking is minimal. 

As an adult, I'm much better at socializing, but still very much an introvert. I prefer the company of animals, and have quite a few of them. I have trouble with reading people's expressions and other nonverbal cues. I'm much more comfortable with written communication than verbal. I have difficulty finding employment because I'm not very good at interviews. I have 3 children and am currently staying at home to care for them, though I would very much prefer to have a job. My first two children are very social, but my youngest seems more like me, and was also very slow with his language development. I had him assessed because I was concerned, but he passed the assessment, since he is very intelligent and he does make eye contact, though he is a little delayed with his language skills. At age 3, he didn't know which of his family members were boys and which were girls, because he'd never picked up on that, and now at age 4 he still uses he/her for everyone, never using she or him.  He leaves out articles and any other words that aren't essential for getting his point across, but he knows numbers up to 100 and how to add. He plays Pokemon Go with me and knows which Pokeball to use based on their size, with numbers in the 100s or 1000s. He's also extremely stubborn and has meltdowns if things don't happen the way he wants, sometimes lasting for half an hour or longer.

Should I try to get a diagnosis? I don't like ambiguity and I would like to know for sure one way or the other, but the whole diagnostic process seems ambiguous and open to interpretation. It seems like it ends up being the opinion of the doctor. If I can make eye contact and don't have stimming behavior, will the doctor just write it off as normal, like they did for my son? Is there any benefit if I did get the diagnosis, as far as assistance with passing an interview to get a job, for example? I am living in the US, in a right to work state where you can get fired for anything or nothing at all. I kind of got pushed out of a previous job because of a coworker complaining about problems between us that I wasn't even aware of. Maybe having a diagnosis would help me in a situation like that, to explain that I need to be told directly what the problem is. Or maybe I'm not really on the autism spectrum at all and it's something else - but I do feel like I'm different from most other people, and I'd like to find a way to describe what it is.