I had my neck surgery done in May. They had to widen the spinal column and get rid of bulging disks. They went in from the back. I had an Xray done calle a milogram with dye so the suregeon could see what pathway to use. I was told that headaches were a side effect of it was headaches. I seem to be having the headache side effect to this day. How long should I be having this side effect?