Listen to the children. Sometimes you'll get a valuable heads-up.
As we were driving home from church, VFDKitty was reported to have a tooth poking out funny. When we got home, she was brought up to the Master Bathroom (mine) where there are coincident bright lights and a big countertop. I had my Darling Wife hold the cat down on the counter while I held the cat's head. The poor thing had a lower canine tooth poking out the front of her mouth, with the upper lip resting on top of the tooth. I gave it a litle tiny tug and the tooth came right out.
The cat was none too happy about these shenanigans, but within a few minutes was reported to be back to cheerful and playing. My Darling Wife said "well that would explain why she hasn't been eating her food." I wouldn't want to eat anything either! I gave her 1/4 a baby aspirin in some peanut butter and she should be just fine.
Unless she's dying of somthing nasty with one of the symptoms being a tooth fall out. But more likely, she just snagged the tooth on a dog or something.