Nipple pain is not a sign of pregnancy, during pregnancy due to changes in hormone levels in the body, which can lead to nipple swelling and pain. There are many causes of nipple pain, including three main aspects: First, when the nipple receives external stimulation, such as cold or touch, it can cause physiological hardness, which can be accompanied by painful discomfort when touched, but is a normal physiological phenomenon. Second, acute mastitis, an acute purulent infection of the breast tissue, can form a breast abscess when the scope of infection is large, the nipple is congested and enlarged, and accompanied by severe pain. The third, cystic hyperplasia of the breast, the typical clinical manifestation is bilateral breast swelling and pain, and accompanied by nodule-like changes in the breast hyperplasia, when the pain is intense can spread to the nipple, the phenomenon of nipple pain. The painful nipples are not necessarily a sign of pregnancy. If you want to know whether you are pregnant or not, you should go to the obstetrics department of a regular hospital and have an HCG or gynecological ultrasound examination to make a clear diagnosis.