When should I see a doctor? When facing the following problems in adulthood If your period starts before the age of 8 years. She reached the age of 15 and did not start her period. The course did not start within 3 years of the emergence of breasts. If menstrual periods are not regular within the first 3 years. When you experience the following problems in the menstrual period: If the symptoms are severe which hinders the exercise of daily activities. If painkillers do not help relieve menstrual pain.