Although painful, postpartum cramps are totally normal. They happen when your uterus is shrinking back to its normal size after you give birth, which can take up to six weeks. Postpartum cramps can last 2-3 days, but not every woman will experience them. The pain can be worse the more children you give birth to. There are ways to alleviate the cramps, such as heating pads and anti-inflammatory drugs that are safe to take while breastfeeding. Talk to your doctor if the pain becomes unbearable and if you have any unusual discharge or have a fever.