Hello dear user! I have gone through your query and understood your concerns! Thank you for sharing them on healthcaremagic. Let say that you haven t taken that emergency contraceptive properly. There is no reason for thinking that the pill will be more effective if you take both of them in the same time. The dosage is enough, and the second pill should be taken after 12 hours as prescribed. Anyway, i have to say that these pills prevent from pregnancy at about 95% of the cases. As you see, always exist a 5% of the cases when this pill fails. Delayed period may be due to the pill side effects, since it is already known that it might lead to menstrual cycle disorders. But, to answer your question, i think you should have a pregnancy test to rule the pregnancy out. I hope this answer was helpful to you! Please kindly rate it as helpful and write a short review about your experience with me! I would appreciate that a lot. Thank you and best regards! DR ERIOL.