DD is three in a fortnight. She still BFs once in the night and usually once in the day.
I have had only three periods since she was born. One time I didn't ovulate. I can tell when I do because it really hurts to feed her for about a week when it happens! They were quite spaced out, about every 6 to 8 weeks.
I think I am a bit unusual though in that I didn't start to menstruate again after having her for over two and a half years. So my experience is probably no use as to what is normal really!