Funny, I'm purely self-taught and have worked for little local cos as well as big ones such as Pepsi & Bear Stearns (as a consultant at $hundreds per hour). Never had any problems with the fact that I had zero "official" credentials whatsoever.

They all hired me for what I had already shown I could DO.

I even put on my resume "School of Hard Knocks" - back when I actually had a resume.

If I were you, I would wonder that the common thread is in your experiences.