The bottom left of my teeth have felt crammed, bruised, pressure when I bite down and I only notice this at night before I go to sleep and when I wake up. It is not painful, just discomfort and I have no idea what it is or what it could be. It started about 5 months ago. Any suggestions? I have been to two different dentists, with x rays, and they say nothing is wrong...but there sure is something different going on.