Without knowing all the details, it's prolly unfair for me to say that your dentist is a total bonehead. But I gotta say it anyway.
If you're in pain, your dentist needs to address the issue. Sensitivity to percussion or pressure (like chewing) is a bad sign. You can have some sensitivity after a filling but it should subside fairly quickly and not prevent you from eating.
You should go to another dentist immediately. Ask all your friends for a reference. Or take a spin into the U.S. and pay cash to some real progressive dentist.
Did you have such sensitivity before you had the filling or was it only after? Is it a silver (amalgam) filling or a white (composite) filling?
Your dentist may have accidentally damaged your pulp or maybe it was already infected and now it's acting up because the filling placed trauma on it. Regardless of how it got that way, you require immediate treatment for the pain.
Provided you get to an endodontist immediately for a root canal (probably what you need) and get the tooth crowned, I see no reason to stop your cycle. (Unless of course you feel better by re-starting.) Your pain should subside within a day if you are treated appropriately.
Just try to find a dentist who really knows what they are doing. You will be okay in a day or so.
And don't let any one tell you they need extract your tooth unless it's severly fractured.