I breastfed lo till he was 11 months old and he weaned off. He is now 16 months old. Well, since my period came back the cycle has shortened. I was a regular 27 day cycle, now it is about 23 days. Is this normal?. I did not breastfeed my other two sons past 6 months so this is new to me. Will it fluctuate for awhile. We are thinking about TTC #4.