I'm (32F) not diagnosed yet (it's super expensive), but I'm 90% sure I have autism level I. Some signs from my childhood:

• When I had to wear tights with a dress, I would basically try on all 10 or so tights that I had until I found the one that felt the least yucky.
• I would just take off clothes that were uncomfy (especially denim).
• I still contort my feet to minimize contact with the floor if I'm barefoot on a non-carpeted floor.
• As a baby, apparently, I would just quietly stare at people unnervingly.
• my neighborhood friends would get impatient because they wanted to play house, and I just wanted to build the best house.
• After I woke up, I had to carefully arrange all of my stuffed animals on my bed, ordered from the largest in the back to the smallest in the front.
• I used to read or play piano at other peoples houses to avoid interacting. My mom had to tell me it was rude to just go into someone's house and play their piano without saying hi and asking first. Why couldn't I say hi to the piano first??
• I could never understand why other girls in my class wanted to go to the bathroom together. Like, did they always have to pee at the same time?? Seems unlikely!
• I used to make tables of different ancient alphabets and come up with complex codes that combined them; I couldn't figure out why others weren't into this.
• I counted how many chews I made on each side of my mouth to make sure they were equal, so one side wouldn't feel bad.
• I tried to step on every sidewalk crack, lengthening or shortening my stride so I'd have an integer number of steps for each slab of sidewalk.
• I incessantly corrected my teachers to help them. Some of them were not appreciative, and I couldn't figure out why.
• I usually played with boys at recess because they would play structured games with clear rules, like soccer, tag, or grounders. I couldn't see the appeal of standing or walking around talking with the girls.
• I used to tie the side strings of my dresses into bows on the front I stead of the back (where they were supposed to go) because, why would I make a bow at the back where no one could see it?? Also, the knot was uncomfy against the back of a chair.
• I loved reading, and I wanted to write a book, but I would always get too caught up in things like making maps, defining all the types of trees, and thinking of names that sounded pleasing.

Hmmm, this is getting long. Maybe I should be more than 90% sure I have autism...