A little over a year ago I had a crown fitted for a tooth that had a root canal done. I had no pain with the tooth after the root canal which was done about three years ago or with the crown. The last few days I have noticed that I have pain in the tooth and it hurts a lot when I drink something hot. It doesn't hurt when I bite down, but when I press the bottom of the tooth with my finger there is a slight pain. I was wondering what this could mean.

It could mean that the root canal has failed. You should have an x-ray of that tooth, there is probably an infection at the tip of the root.