Abnormal pap smears should be retaken, because abnormal cells are signs that something might be wrong. Also, if your period all of a sudden starts acting strange. For example: if you werer normally regular and right on time, 7 day cycle, and you can predict right when you would start, then all of a sudden you are having 4 day cycles or 13 day cycles and you don't know when it will start. or just the opposite of that. If you are concerned, ask your doctor. It doesn't even have to be the ob/gyn, your regular dr. will be able to tell you as well.