How to tell whether chest swelling and pain is a period or pregnancy can be determined according to whether the menstrual period is delayed, the duration of the pain and the early pregnancy test. 1. Whether the menstrual period is delayed: women who are pregnant will have delayed menstruation or menopause, but delayed menstruation does not necessarily mean that they are pregnant. 2. Duration of chest pain: If the chest pain is before the vacation, the pain can be relieved by itself after the menstruation. But after pregnancy, the chest pain will last longer because it is related to the change of hormone level in the body, but the pain is usually not particularly serious. 3. Early pregnancy test: You can use early pregnancy test paper or blood test for human chorionic gonadotropin two weeks after intercourse to test, you can initially determine whether the chest pain is caused by regular holidays or pregnancy. Those who can’t tell whether chest pain is caused by vacation or pregnancy can go to the hospital in time to be examined by a professional doctor for judgment.