How fast did you get pregnant?

My period just finished and I'm now in my first month of trying to get pregnant! ...A little frightening, what if it happens immediately - what if it doesn't? My period has been irregular since I stopped taking birth-control pills four months ago. What is your experience? I heard that if you don't get pregnant immediately after ending your birth control pills, it may take quite some time, as the body has to find its own cycle?