Could there be a dirty apartment in my building?

I was laying in be watching tv and then I saw something crawling on my blanket, and sure enough when I turned the lights on, it was a roach. Eeewww!!!!
Well, my apartment is spotless. I have no food left out, my kitchen is scrubbed daily, and I vacuum every other day.
I live in Colorado, and I have never seen a roach out jere before. I have been told that you have to be dirty in order to have them out here.
Could it be that there is a dirty apartment in the building?