Pain when touching tooth after root canal and crown

I had a root canal performed on tooth #13 in March due to sensitivity and slight pain when tapping. Had a crown put on in April.  My crowned tooth now is very painful whenever something hard bumps against it (toothbrush, cough drop, etc.) It is not painful when chewing...just slightly when chewing granola or something of a harder consistency. The most painful is when I floss...NOT when I hit the gum, but initially when I put the floss between both sides of the crowned tooth and when I pull the floss out.  No pain on the gumline. When I wiggle my tooth with my fingers, there is pain as I go back and forth, but no real pain when I press up. When I tap on my tooth, it is also painful.

I went to the endodontist who performed the root canal...he did and xray and a CT and didn't see anything fancy. Any advice would be apprecieated.

[Jerome Tsang, DDS]

Seems to be a bit too long for some sensitivity problems after a root canal.  Is there a possibility of a fracture in the tooth?  Those aren't usually detectable though.  Its hard to see a fracture on the x-ray although you can sometimes put the clues together and come to that conclusion.