Thank you for telling us that as I had no idea. My mouth gets sensitive over stress, my menstrual cycle, and sinus/colds. It only makes sense that would probably cause sensitivity, too.
if you had a composite placed (white filling) and it is on a back tooth, you can ask the dentist to replacer it with an amalgam (silver) filling with some sort of sedative base-- tjhat is if it is still uncomfortable after a week or two. composite fillings can cause alot of sensitivity.
I had a cavity filled about 3 months ago and it was uncomfortable for about a week. The tooth felt very sensitive. I just tried not to chew on that side and it went away after about a week.
I don't know the type of restoration that you received. My feeling is that it was a composite filling(tooth color). These fillings can be sensitive for a fairly long time(that can vary). I think you should wait a few more days and if there is no improvement, especially if you can not bite on it return to the dentist and have it redone.