Tremendous pain in head and nerves while flying? Hi,

I feel heavy pain while I fly in plane. This happens especially when the plane starts landing. I feel the pain in the skull in the upper part of skull over eyes. The pain is unbearable and I feel tremendous pressure in my head and nerves start heavily stretching. I feel that the nerves in the head will blast. Please note that I feel heavy pain in the area near to eyes both sides of the face. This happens only at the time of landing and not the take-off. I am really worried of this situation and I am scared of flying now. I've felt this type of pain eight times of out of nine times I flied. Please provide some suggestion what kind of problem it could be. Please let me know if you have any idea about what kind of problem I may have or if any more details regarding to my problem.

Summarized question: Why do i feel severe pain behind my eyes when landing and how can it be prevented?