Thanks for writing in.
I read your problem,i would like to tell you that pain after root canal treatment
could be because of following reasons-
2.Infection left,because of improper cleaning of canals.
3.Infection of adjacent tooth.
One more thing you did not mentioned that whether you got the crown over that tooth after root canal treatment.
So i will suggest you please visit back to your dentist
and get the thorough examination done including x-ray of that tooth.
Nothing to get worried pou need not to take a neurologist's consultation.