How long it takes for symptoms to appear before menstruation depends on the individual. Some people may have no symptoms at all; others may experience significant discomfort a week or so before menstruation. Each person’s physical condition is different before the onset of menstruation, and therefore the symptoms may vary. Some people may experience lower back pain and stomach cramps, while others may react with physical fatigue and weakness, nervousness, and excessive mood swings, which may occur about a week before the onset of menstruation. If the symptoms are not obvious before menstruation, you should pay attention to rest and keep your body warm, but if the symptoms are more obvious, you are advised to consult a doctor in time for examination and treatment.