unexplained sudden tooth pain

I woke up yesterday and my jaw was sore.. I thought that i had just been grinding my teeth.  the soreness subsided yet one tooth became more sensitive.  By the end of the day i could not let anyhting touch it! (even pressure from my tounge irritated it) i went to the dentist the very next day and i had previously had a cavity in that particular tooth (i just figured the filling had come loose, or gotten worse). they did an x-ray (tooth and root) they saw nothing that apperared to be wrong.  i am 24 and was blessed with the my fathers teeth.. (not a good thing) i have had 2 root canals and nothing could touch the pain that this tooth was causing.. when i took a deep breath even air made it throb.. the pain would last a minute or so then would subside.  they gave me antibiotics and said to see what happens.  the pain has decreases a little but the tooth is still very sensitive.  my dentist had no idea what it was that was causeing this... she said that if it didn't get anybetter that the smart choice would be another root canal, or a small chance that it might be fractured but they did not see any evidense of that!!  have you ever heard of this?? i am healthy, do not smoke, no health problems!  please help!!
beckylou664

[scottma]

Seeing an endodontist is advised.