Having a few minor aches and pains during pregnancy is nothing to be concerned about. They occur because the ligaments and muscles of your pelvis are stretching to fit your ever-growing uterus. This can cause some discomfort but should be manageable. If the pain you're experiencing does become crampy, like period pain, and there is any bleeding, or if the pain becomes very severe and constant, then you should go to the doctor or the hospital to be checked. You will be examined to rule out a miscarriage or ectopic pregnancy.