i unfortantly was unable to breastfeed my daughter. i did not produce enough to nurish her. during my attempts to feed her i didn't have a period until 2 or 3 weeks after. they were less then normal. off and on spotting like you discribed. they did soon become regular like they were before. a friend of mine breast feed past 2 years she did actually start having her periods after 20m and they did the same. when in doubt thought have it checked out. they did tell me however it can take a few months for your body to get back to normal.