Taking my baby to the Vet

We have a 5:15 appt in PA today at the animal hospital. My 10 year old Rottie suddenly stopped eating yesterday morning. She never turns down food. We switched her over to a wet based food because she obviously had trouble chewing then stopped eating all together. I think she either has a bad tooth or a sore jaw from something getting wedged between her teeth, although we looked and did not see anything last night.  Worries me! I have a lot going on right now and really don't want to loose her.
She is all I have left of my Rex, the three of us used to play together....but we do what we must do!
For those of you that are animal lovers, I will keep you posted.
I will know more this evening. Say a prayer will ya!