While lower back pain is very common, delayed pain from complications of epidural or spinal anesthesia is quite rare, especially after years without any problems.

CNN: Can C-section anesthetic lead to low back pain?

Sudden lower back pain years after epidural or spinal anesthesia is more likely to be caused by a recent injury, heavy lifting, poor posture or positioning (such as during sleep or while carrying a backpack), or stress on the bones or muscles.

CNN: Can C-section anesthetic lead to low back pain?