From age 10 through most of my teen years, I could spend hours looking for four-leaf clovers in an open field, neglecting opportunities to socialize to do so, and I still sometimes like to do a little four-leaf-clover hunting today. And I'm just a quirky NT.
Special interests are only one feature of an autism spectrum condition. To be autistic you would also have to have a certain measure of other symptoms, like communication issues (which I actually did have as a kid, though probably to a lesser degree than most autistic people), difficulties with cognitive empathy or mind-reading (or at least the appearance of such difficulties if tested in a standard way that would be easy for NTs to figure out), sensory processing issues (see the thread with videos about what life/walking down the street feels/sounds/looks like when you're autistic), and repetitive behaviors and difficulties with change.
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Right planet, wrong country: possibly PLI as a child, Dxed ADD as a teen, naturalized citizen of neurotypicality as an adult