PAINFUL after root canal

I recently had a root canal performed on a back top molar due to strange pain when biting, xray looked ok. firstly the tooth was filled and was crowned as the dentist said i "might" have a fracture and as this was a big filling best crown it, pain did not go away so he performed root canal, removed nerve that he said was swollen. one canal was done and i was over the moon, came home with no pain (Yippy pain free) I could now bite eat and chew on that tooth but carefully as still the other canal needed doing. the next canal was done, all went ok but some pain along the proceedue as he didnt give me a local, at the end it felt like the drill went right through the root into my head, hurt so bad i yelled and ended in tears, he said thats a good sign as its life in the tooth (i had a different view as it hurt a lot!)
anyway came home, that night tooth had a gnawing pain, alls ok though as some pain expected but the next day the pain increased, its now 3 days gone and its painful most times. NO i can chew on the tooth wiggle it and all sorts and no pain (not that im doing that but i have given a little test) its just a throbbing pain.
i called the dentist and he said he wants to know how it is in 24hrs as he said the next xray says it might have a fractured root and some of the filling went through the root, if it is fractured why doesnt it hurt when i bite or wiggle it, its just a throbbing feeling. you know that tooth ache feeling when you have a bad tooth, where you want to punch the tooth out or are tempted to get the tooths out yourself!
any suggestions please, should i expect this sort of pain, might it go away ect.
im living on pain killers at the moment to get some relief
thanks in advance for any ideas and views