It sounds like the root canal wasn't done right from the beginning. I know you trusted the dentist and probably thought he could do it. If he wasn't an endo, maybe he wasn't qualified. If I was in your shoes, I would be fuming to lose a tooth over a bad root canal. I know with crowns its tricky because you get fitted with temporary crowns and alot of shaving involved. I can believe how they made it seem it was your fault, but it's not. They never seem to accept responsibility.
With my teeth being shaved down too much. It is just on the surface. He shaved down the teeth more on one side than the other so my teeth from top and bottom don't fit right together. There is not sensitivity luckily because it's not near the nerve to cause pain. It's more the shape of the teeth that was ruined. All the dentist(including my current one that I got referred to from a friend) said "let it go" stop thinking about it. But the point is my natural teeth fit perfectly together before from top to bottom, left to right. Now because they don't, my teeth hit each other wrong and that hurts. See he did nine teeth at one time and it just was tooo much. I'm angry because now I have to live with deformed teeth that don't fit right together and there's nothing anyone can do. One dentist just said well it's different from one side to another -- SO WHAT with an attitude like it was me. I mean I could get them replaced by crowns but this would involve more work(and you know what that means, if it gets botched noone can help you).
Good Luck let us know how the tooth heals. My friends that have had teeth pulled have said you get use to it and you won't even notice it in time. Also, I found my current dentist by asking friends and co-workers that were worked on by the dentist if they were good or not. So maybe you can get a good referral if you still have problems finding a good one. I got the bad dentists that just were after my $$$$ from the yellow pages. People have told me NEVER just pick one out of the yellow pages like that.