No menstrual cycle S/P ceasing breastfeeding

I stopped breastfeeding 3-4 weeks ago (until my baby was 17 mos.) and still have not had a menstrual period. Additionally, I pumped 3 days/week + breastfed(...I work part-time) up until this time. We would like to try for another baby, but I am fairly certain that the odds of conceiving are low. Should I be worried? I have read that it can take some women as long as 2-3 years for the return of their menstrual cycle. We became pregnant very quickly with baby no. 1 and pregnancy/delivery were both uneventful.