Generally people speak about root canals as being terribly painful because they were in terrible pain when the needed to have it. In your case, why wait for the pain to get worse?
Some people will have some discomfort after the procedure but it's nothing that OTC pain relievers won't take care of.
Find a dentist that uses digital endodontics. Or even go to an endodontist. You may need to have your current dentist give you a referral (but maybe you can get a little satisfaction letting him know that you would rather see a specialist than him)