Tooth hurts after root canal.

I did a root canal on my upper right first molar and it hurts since the first day. It has been nearly 2 months now and my Dentist had placed a crown on my tooth yesterday. I'd told him that my tooth hurts two weeks after my root canal treatment, he said everything is fine. My crowned tooth Hurts when I chew on food. Sometimes, my teeth from lower/ upper jaw will have a sore/ pain feeling.