Hi, Thanks for writing in. Your pregnancy has been over a year back and you should have made complete recovery from any problems arising out of the surgery at that time. Spine is made up of small bones aligned on top of each other and nerves originating in the spinal cord and exiting through holes between two bones. There are a disc between every two bones which provide cushioning. When the disc gets displaced and causes pressure on the nerves then pain is felt. The commonest reason for back pain at your age is muscle spasm but nerve related pain cannot be ruled out without doing a clinical examination. A X ray is the basic investigation and will show any muscle spasm or disc space narrowing. If strongly suspected then a MRI might be required to know if you have nerve pinching at any level. You can try using heat pad and gently applying ointment containing pain reliever and muscle relaxant over the area where it is hurting in the back.