numness in lower lips and chin

One day suddenly i started paining in left side of mental foramen . when i touch the spot the pain increases...after 2 days i got the feeling that my left side of lower lip and chin is swollen. when i look in mirror nothing found. it was looking normal. then i went to doctor..he gave some antibiotics for 5 days.. but nothing happened except got more burning sensations in mouth cos of the antibiotics.. then the doctor suggested to show to a dentist..very next day i visited to dentist..1st she gives me antibiotics again.. after 3 days of taking the medicines..i again visited to the dentist..then she took x-ray and done rote canal for one teeth.... after that pains stopped partially. during the period i stopped taking antibiotics..still i am having numness in chin and lower lips.. meanwhile i visited another MD doctor..she suspected its  tribunal nuralgia..and asked to take pregator for 10 days.. but after 15 days..still the condition of numbness is same. sometimes in day it feel like burining in my lips....wt next??? i m comfused  now..