I am sorry for your pain.I am having a tough time of things right now too. But I offer you low pain wishes and some hugs
The t.n. nerve starts at the base of the brain stem. and it most surely can come from an injury to head or neck.I know of other who had injuries to head and or neck and got t.n. from injury. also other who got t.n. or worse from brain surgery. hope this helps you. and I hope others come and lend their info to you.
Low pain at you
PEACE
BMW