Pain for several weeks after having a filling put in, what's going on?

It's been about a month since two of my teeth were filled. I was told they were very small cavities and at first it hurt and was sensitive and it seemed to improve. Then, I found that everytime I bite down on my teeth or chew hard foods, the tooth hurts. Then, it's weird, because if I brush my teeth, that seems to help the pain some. At times, when I'm not eating, I don't feel the pain, but then if I eat something, there it is again. Then, at other times, it's just a lingering and irritating pain. I'm going back to the dentist and am very frustrated. If this guy doesn't know what he's doing - it's the second dentist that has tried to butcher my mouth. It seems dental care is already a situation where you either pay 100% of the cost and go to a very expensive dentist who will do a good job - or accept the insurance coverage I have and go where they tell me - and get butchered. Is that how it is? Maybe I'm just paranoid now and should give the dentist a chance to look at it - if he tells me I need a root canal after saying I just had a little cavity and was having no issues - I'll just go broke for the expensive dentist that I know - is good - who gave me a good second opinion last time. What do you think? This would be the second time I went and paid $200 for a second opinion. This is an outrage!
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Your problem could be a number of things - the pulp of the tooth could be inflamed - this can happen when even a small hole is filled as no matter how good the dentist the drilling will irritate the nerve. It could be the tooth has developed a crack in a weak spot, or it could indeed be the nerve is dying off and will need a root canal. If it's any consolation, this can happen to absolutely any dentist, and it is tricky to predict which teeth may give trouble after treatment. If the pain isn't too bad or constant, removing the filling and dressing with a sedative temporary material may settle it down without the need for a root canal. Or it may enable the dentist to see if a crack has developed under the filling and to remove the cracked bit, eradicating the pain. On the bright side, the filling may even be just a bit high and need trimming down a bit. Good luck!
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