The strangeness of strangers

I'm talking to a bus driver, trying to figure out where to get off a bus on a road that I know, in a city I've lived in for many years.  I have a strong, clear, English accent, and I'm dressed in my best impression of normal.  A stranger comes up behind me as I get off the bus and asks:

"Are you Polish?" 

I reply:  

"No, I'm autistic."