It is possible that the pain in your lower abdomen is caused by your menstrual cycle. Trying over-the-counter pain relievers like ibuprofen, staying hydrated, and gradually increasing your fiber intake may help with your symptoms. It is important to monitor your symptoms and seek medical attention if they worsen or if you experience any alarming symptoms. Additionally, missing contraceptive pills can affect their effectiveness, so it is important to follow the recommended guidelines for missed pills and consider using additional contraception if needed. If you have had unprotected sex recently, contacting a healthcare provider for further advice is recommended.