Toothache After Cavity Filling Deep Filling Cavity Hurts After 3 Months?

Deep filling cavity hurts after 3 months? - toothache after cavity filling

So a few months ago I received a cave / deep filled with big teeth, my last (but not) wisdom. It is so great that even on the sides, there amalgam sample. Anyway, when I arrived, he did not do much damage, until recently it has begun, a little hurt.

Finally I said to my dentist and he thought the filling was too high for sand. Well, I'm worse than ever. Is this normal? After some parts were demolished, my toothache and forth and there is extreme sensitivity. When I drink cold water pulses / feels like a brain freeze, but in my tooth. It's terrible when it comes to overeating. Is this normal (because of the sand) down or I need a root canal?