J.D.
a group of BF'ing moms and I recently commiserated about this and the general consensus was that most of us BF'ed for about 10-11 months before we got our periods. Some of them didn't get their periods until after the child was completely weaned (for some women, 2-3 years!!!) Don't worry about it and thank your lucky stars! But remember, you won't know you are ovulating when you finally do start your cycle, so you'll still need to be careful if you want to avoid another pregnancy for now.
J.