It took my body/menstrual cycle over a year to get semi back to normal. In fact, my cycle didn't go completely regular (like I always was) until August 2008. I had my abortion in Oct 2006. One month my period was a week early, the next it was a week late. I think I went through about 10 pregnancy tests worrying about it! I also still got pregnancy symptoms around the time of my period for about 6 months afterward.
Everybody is different though. Wait a little bit longer, and if it doesn't come or you are worried, then see your doctor.
