I have been on microgestin fe 1/20 for over a year and now have been spotting for 12 days (first 12 of this month's pills) Have a colposcopy coming up this week( for mulitple abnormal paps), which i guess i will now have to postpone, and am worried. I have never missed a pill, and have only waivered my time by a max of two hours. what could be the cause?