Hello dear Understand your concern. I think it is side effects of Birth control pill as you are using first time. Pain in uterus may be due to first sexual intercourse/rough sex. Note the common side effects of OCP: Intermenstrual spotting Nausea Breast tenderness Irregular periods, nausea, headaches or weight change. Headache Malaise, weakness Weight gain Mood changes: due to hormonal imbalance Decreased libido Vaginal discharge Visual changes Chance of pregnancy is less. But you can check by Urine HCG kit after 7 days of missed period. Advice: Take tablet meftal saps three times a day for 2-3 days or when pain All this side effects will decrease after 2-3 months of regular use of pills as body get adapated Take healthy diet Avoid excessive stress, alcohol, salt and caffeine. Do regular exercise. Use safer sex practice and maintain hygiene after and before sex. If persists , you can use other contraceptive methods like condoms Hope this may help you. Best regards Dr. Sagar