Hi, According to the description the possibilities of your delayed periods are: - Usually contraceptive pills are advised to start during the first five days of the menstrual cycle, so that the cyclical pattern of the menstruation will be maintained. As you have stated the contraceptive pills one week after your menstrual period, that might have led to delay in your next menstrual period. - Rarely urine pregnancy test kits can give false negative results. So, to exactly rule out the possibility of pregnancy, better to go for a blood test for pregnancy or ultrasound. Blood test for pregnancy if serum beta HCG levels are less than 5 mIU/mL that rules out the possibility of pregnancy and you can wait for your periods for a few more days. Ultrasound helps in ruling out the pregnancy and also in finding the possible causes of delayed periods, depending on that further treatment can be planned. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Sree Gouri S. R., OBGYN