Painful tooth To root or not to root

A couple of weeks ago one the lower right molars became extremely sensitive to cold liquids. The dentist said the filling was broken in one area and should be replaced, and since it's a very large and deep filling, he recommended inlay. Two days before my appointment the area started to hurt so badly I couldn't sleep or concentrate at work. Nighttime worse than daytime. The filling was done yesterday, and said that the nerve was not exposed so root canal may not be necessary. But 24 hours later it hurts just as much and even a little more. I'm afraid I'm headed to a root canal - should I do it ? Should I wait a week or so to see if the tooth is healing ? The pain at times is almost unbearable, and affecting my general feeling as I can't sleep. Thanks for all replies. Tweet