Stomach pain after childbirth can be caused by several factors. Common problems include:
Your uterus is contracting and shrinking back to its normal size. You will feel some dull pain and some sharp pains as a result of this. Some of the pain may be in your back as well. Most moms will experience the most intense of these pains in the first week after giving birth. The uterus can take as long as four to six weeks to return to its normal size, however, so you may still be experiencing these afterpains during that time.
Note that these pains will be stronger when your baby is breastfeeding, since this stimulates the release of oxytocin which causes the uterus to contract. Since you're a first-time mom, your pains will likely be less than a mom who has had more than one pregnancy. A mom who has given birth more than once will have less muscle tone in her uterus.
You can remedy these pains by applying a warm heating pad (you can make your own rice sock for this) or taking a pain reliever approved by your health care provider (be sure to mention if you are nursing.)
Another contributing factor for stomach pain is that your bowels are getting back to normal. If you had any kind of anesthesia or if you are taking a narcotic for pain like hydrocodone, this can compound the problem of constipation.
To remedy this, you should make sure you are eating lots of fiber and drinking plenty of water. Also, make sure that you are walking some each day. If you haven't had a bowel movement for more than a couple of days, talk to your health care provider about taking a stool softener that contains docusate (like Colace or Docusoft).
If you had a C-section, you will certainly feel some pain as the incision and internal wounds heal. Make sure you get enough rest and don't put too much strain on your stomach. Take all pain relievers as directed. If the pain really bothers you, it's better to stay on top of it by taking your dose every 4 hours, for example, than to delay a dose and have to wait until a late dose kicks in. Make sure that you're not doing too much. Invite friends and family over to help with housework and other tasks, but make sure they don't hinder your need for rest. If necessary, hire professionals to take care of yard work, shopping and cleaning so you can heal.