I've never taken Plan B, but I think the first thing I'd do is call the pharmacist. It's been my experience that pharmacists generally know more about meds than the doctors who prescribe them, so I'd start there. A call to your gynecologist might also be an option. Bottom line, you don't sound like anyone fully explained to you what might happen and what to expect, what's normal, etc. What are the time parameters? How long after you take the pill are you supposed to get your period? Are you usually regular? Do you have light periods? These are all questions that might make a difference, and you really need to talk to your pharmacist and your doctor to get the answers you need, I think. Good luck!