The main reason for nipple damage and soreness during breastfeeding is an incorrect feeding technique. If it is your first baby, then you may not know how to breastfeed your baby properly, so ask your midwife, nurse, or doctor and they will gladly help you. It is important to get your baby lying in the right position and latching on to your nipple properly.
If breastfeeding your baby is painful for you, then it is very important that you rectify this immediately. This is not only to prevent feeding being uncomfortable for you, but also because your baby will not get enough milk and feeding will take a lot longer.
For pain-free breastfeeding, your baby’s mouth needs to be wide open, allowing him to take in enough of your breast so that your nipple is lying between the back of his tongue and his soft palate, which is situated right at the back of his mouth. This way, his tongue will press against your breast instead of your nipple.
If his mouth is not wide enough and your nipple is not far back enough in his mouth, your nipple will be rubbed repeatedly by his tongue and become sore, sometimes causing the skin to crack. This is known as cracked nipple.There are lanolin creams that you can use to soothe sore nipples. These are safe and non toxic, so you don't need to wash them off before feeding again.
For your baby to get milk during his feed, his tongue needs to press down where the milk collects - on the breast tissue right behind the nipple. Sucking on your nipple alone will get him no milk, as the nipple is simply a tube through which the milk passes.