Wisdom tooth headache pain complication

Hi,

I had a lower wisdom tooth out 18 months ago and for the last year I have had a nerval pain over the top and down the sides of my head. I also have a slight soreness in the same jaw which runs underneath it. I would like to know if this is a complication of the tooth removal or is this the last lower tooth causing trouble? The headaches go behind my ears and on the top of my head, rather like nerval pain, a dull ache. It sometimes feels like either my head gets cold or hot - strange feeling. Is it the removal of the old one do you think? I am worried about having the other one removed if this is from the first one.

Thanks

Robert