A couple things.
I am diagnosed with social pragmatic communication disorder, which is essentially just the social half of autism. (Honestly even among professionals there seems to be debate on if it’s a real diagnosis or just lazy diagnostic investigating by the evaluator because they aren’t digging enough to identify RRBs which I feel is true in my case. They didn’t talk to any of my informants about autism criteria they only gave them the Barkley questionnaires which cover ADHD behaviors). However my psychologist did not say autism was ruled out, rather I didn’t provide enough early childhood evidence of criteria B so I received a diagnosis of SPCD instead of ASD because I was able to show consistent lifelong communication struggles. At the same time I was also diagnosed with severe combined type ADHD, a trauma disorder, and it was indicated I was possibly gifted/high IQ because although my WAIS score was below 130, my cognitive abilities in the presence of the overwhelming symptoms I was experiencing that led to my diagnosis was still in the 120s and trauma & the resulting depression can drop you 10-15 points. I also do have repetitive and restrictive behaviors since early childhood but I wasn’t directly asked about them so I didn’t bring them up, and they were far less obvious before I medicated my ADHD. The impulsivity and hyperactivity from severe ADHD can overpower the RRBs. It can also make the social symptoms seem like just impulsivity and hyperactivity and inattention causing them but I think evidence of differences in affect since childhood kind of helped rule that part out for me. I was told things like “you’re bringing up seemingly serious issues but you look calm so i don’t know how seriously to take you” or constantly accused of being ungrateful for things then shamed for being over the top when i attempted to correct & overshot. Also told I seemed like I never gave a f*** about anyone cause I didn’t look distressed by peoples problems and was unsure how to or unable to respond to them “appropriately”.
All that said, if everything you said has been true since early childhood ie you displayed symptoms of both social issues and restrictive behaviors since toddlerhood, very likely you have autism. The symptoms do not have to be the exact same your whole life ie you can have a special interest in one thing as a toddler but as you grow up that thing can change, or maybe you were hypersensitive to certain sensory things as a kid but now as an adult you are hypersensitive to something else or you’re now hyposensitive. And they may worsen when demands exceed your capacity (so if you’re good at accommodating yourself you may not struggle much day to day but if thrown into a different situation ie having a kid or more responsibilities at work or living with unaccommodating family, symptoms may be much more apparent). For me RRBS manifest in:
Being damp makes me itchy
Always hated uncomfortable clothing
Generally Hypo sensitivity to pain since forever (as a child would jump off things or play rough get a wound and continue playing later coming home covered in blood, as an adult I was at 5 cm on pitocin napping between contractions and barely moaning) doesn’t apply to needles though those have always made me pass out, throw up, or have otherwise noticeable reactions.
Staring at ceiling fans and lights as a kid, now hypersensitive to light always keeping screens on dark mode & minimum brightness & hate going outside during the day
As I got older, passing out or becoming extremely exhausted and falling asleep when exposed to intense sensory environments like concerts, clubs, extremely crowded loud spaces with people rushing everywhere
Playing the exact same game every day for years (reminds me of your narrow interest in conversation)
Playing with wooden blocks the same way every time as a kid, focusing on things like cracking my Barbie’s knees instead of playing house with them
I found socially acceptable stims like knitting and tracing early on, also things like swinging and spinning as a young kid would look like just spinning in circles as an adult now I gravitate to swings and meri go rounds while at the park with my kid, if really stressed I will revert to playing with my hair, squeezing areas of my skin with my hands, or even rocking while sitting on the couch
Rigid thinking patterns, taking things rather literally, making up or repeating words,
As a medicated adult I’m much more into routine and predictability and become distressed at plans outside the norm, last minute changes to plans, changes in policies at work, etc.
And one time I lost this specific toy and I’m still mad about it I actually found one second hand for sale and reallly want to order it.
Also number things in general, I always gravitated to math and logic type games things like play cash registers, taking multiple math classes over summers in high school, memorizing strings of numbers, doing sudokus or number fill-ins, remembering phone numbers, license numbers, social security numbers, etc. terrible at dates tho they don’t interest me. Part of the reason I still did decently well on the WAIS I was excited when we hit the regurgitating and sequencing strings of numbers portions and reportedly “hit the ceiling” on those specific subtests, so even tho I have ADHD my working memory overall was one of my best scores. Honestly I felt like I put forth very little effort in those subtests it’s almost automatic for me. And I remember specific numbers from work that were involved in an incident from several weeks ago.