Don’t worry about the “electic shock” feeling when you push on the prior surgery site. You probably have a small sensory nerve that is caught up in the skin scar and will eventually calm down.
Now back pain is different. Remember that you had a large tear in the wall of the disc and a large amount of disc material (the jelly of the donut) that came out. This disc has to settle and accomodate with less shock absorption material. Unfortunately, this takes time. You are at four months post-op. Give this another two months.
Now if this pain is not midline but in the buttocks region on the side of the prior hernation, this is different and most likely residual irritation of the nerve root. A new MRI might be helpful to determine if there is no recurrent herniation. An epidural steroid injection might be helpful in this case.
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.