Oh, yeah, I've been there. I had a couple of dentists that went ahead and DID the root canal and crap when the tooth was split all the way down to the jaw bone!!

Now, I am no genius but even I can figure out that is not going to a good place!! I spent several thousand $$$ on the $#%* thing before they decided it had to be pulled. They sent me to a DDS, 2 hours away, some sort of specialist, to pull it and the tooth had rocked around and gotten so loose (wearing away jaw bone with it) that he pulled the $#@! thing with his fingers!! Then, they wanted to do an implant! But, first, I was going to have to have some bone grafting done to build jaw bone back up to hold the implant in. I said no thank you. We don't have dental insurance. DH was mad at me for awhile over that one.
Now you can see a hole in my smile and I am pretty self-conscious about it.

Sorry folks, I am no fan of DDS!
Could your pain be coming from the numbing shot place healing? Or can you tell that it is from the tooth fer sure?