Pain after Cavity Fillings?

I recently had three cavity fillings done on my teeth. Two on my left side (top, bottom) and one on my bottom right side. I've had the fillings for a little more than a month and it still hurts to eat. Every time I bite down on something hard or even chewy (like gum) there's a bit of pain. My left side feels better than the right, but a pinch feeling is still there. Can somebody please tell me what to do? If it's normal, or if I should go back to see my dentist?