mamanan,
The one good thing out of all of this is that you aren't in pain, anymore. I understand that you are nervous about getting the root canal. I used to have the worst "dental anxiety" (due to something that happened to me at the dentist when I was a child). I would sit in that chair and cry like a 2 year old!
If it helps, I have had at least 10 root canals and 5 crowns. As long as they give you an Rx for pain meds, you should be fine. If you are worried about not getting numb enough, can you find out if they have nitrous oxide? Or, maybe they can give you something for anxiety. A lot of dentists are doing that these days.
Anyway, I hope everything works out for you. I know how scary (and expensive) things can be. Keep us posted!