Hello, Since you had protected sex, you shouldn t be pregnant. Delay in the periods also occur due to stress(emotional & physical), anxiety and poor general heath condition, anemia, thyroid issues, hormonal problems, PID, ovarian diseases, etc. You are suggested to stay well hydrated & take home made nutritious food rich in iron, calcium and protein. Take adequate rest and avoid stress. You can also take supplements. If obese, maintain healthy weight. Stay active. To be on the safer side you are suggested to get a pregnancy test done after waiting for a couple of days. If it is negative, get clinically examined by a gynecologist you may need to get few blood tests, urinalysis and imaging tests to detect the pathology causing you discomfort. You will be accordingly treated. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician