Autistic imposter syndrome
As autism's pretty rare, many autistic people — especially those who can't afford to get an official diagnosis — doubt themselves, even when they intellectually know that it's the best fit to explain their whole life. This is known as autistic imposter syndrome.
Occam's razor
At first glance, Occam's razor seems to work against you, but I think it can just as easily work for you. Try making a shift from "What are the chances I might be autistic? It's so rare!" to "This is the list of traits that I have. What are the chances they all have independent, unrelated explanations, compared to the one simple overarching explanation of me being autistic? That would be improbable!"
Having traits without realising it
Another thing that's helped me is to remember that I struggled with many autistic traits before realising they were autistic traits, so it's not possible that I was just mimicking them.
People often ask me if I'm going deaf because I can't tell what they're saying, even though if anything I can hear sounds too well. Even in high school, I routinely had to ask my friend sitting next to me what the teacher was saying, which understandably frustrated my friend too because then they couldn't hear the next thing the teacher was saying while they were still repeating the last thing to me. So I'm pretty sure I'm not imagining that I have auditory processing disorder, now that I've discovered it's a thing.
In school, the other children mocked what I later thought might have been "nervous tics", but much later realised were actually stims. Clearly, I didn't realise at the time that they were an autistic trait, and very likely hadn't even heard of autism when I started stimming. It was just something I did when I was stressed. Some of them aren't even perceivable to others, like repeating mantras of nonsense stopwords in my head — certainly not something I'm faking for other people's benefit!
I hardly ever use a hairdryer, and it was a dealbreaker for me that I'd only vacuum clean if I could listen to music on earphones at the same time. I listened to music whenever I commuted, and at a sufficiently complex job, whenever I had to concentrate on work. Only much later did I realise I get easily overwhelmed by sounds, buy noise-cancelling headphones, and instantly improve my quality of life. Certainly I wasn't faking an aversion to loud sounds, and somehow hadn't even made the connection as to why I avoid these specific things, not noticing that loud sounds were what they had in common.
Self-acceptance and unmasking
I've apparently noticeably gotten even more visibly sensitive, since I decided to let go of my secrets and shame, and openly be myself. However, that's not me acting more autistic, or even being more autistic — it's me learning to unmask, to stop spending a substantial amount of my energy on pretending I'm coping with things when I'm actually struggling with them. It's not putting on an act, it's taking off the act.
Am I autistic?: Autistic and allistic traits | Autistic imposter syndrome | If I'm autistic, why don't I stim? | Online autism tests | Self-diagnosis is valid
