Chipped molar related question?

I have noticed that my far back wisdom tooth has chipped a few months ago there was no pain for a couple of months but recently my molar has been aching a lot during midnight and the early mornings. The molar has a big chip on one side reaching down to the gum while the other half of the molar looks normal except for the middle of the molar where food pieces become trapped, i brush it to remove the food piece but sometimes when i brush the molar i get this kind of sensitive teeth like pain when i brush over it, the pain is like a pen stabbing from the inside and for some reason panadein forte and amoxcillin seem to be inefective against the severe pain.