Hello dear understand your concern Please note that, there is no contraception that will give you 100 percent protection. As you took unwanted 72 with in 24 hour after sex, there may be possibility of pregnancy around 5 % (success rate is 95 %). But bleeding after taking unwanted 72 is not suggestive of pregnancy. As you took two tablet with in short time, there is high possibility of hormonal imbalance/dysfunction that produce progesterone withdrawal bleeding. It will stops with in 5-8 days. So it is just side effects of unwanted 72 pills. So never use unwanted 72 as regular contraception or so frequently as it cause menstrual irregularity. If bleeding will continue then consult the gynaecologist, get examined and take tranexamic acid to reduce the bleeding. Maintain pelvic hygiene by using V-Vaginal plus wash to prevent the infection. Your period should be delayed by 5-7 days due to hormonal imbalance. If period will delay by 12-14 days from your normal expected period then rule out the pregnancy by pregnancy kit and or Blood HCG. In future use condoms to prevent the pregnancy and keep the unwanted 72 as a emergency option. Hope this may help you Best regards Dr. Sagar