I had a c-section a week and 2 days ago i am have horrible lower back pain and also having a hard time with bowel movements. what could it be?

Many possibilities: Low back pain and constipation 9 days after a cesarean. Constipation is common after a cesarean, due to pain meds and not moving as much. Make sure you are using a good stool softener such as senna and drinking lots of water. Back pain could be from constipation, bladder/kidney infection, soreness from where epidural or spinal was. Call your doc and get seen.