L.A.
I wonder if you are allergic to some type of food, drink, toothpaste, mouth wash? I would do a s Gidget suggested and start off with primary care doctor.
But also start documenting what you eat, drink and rinse your mouth with and the tooth paste.
With the change in produce, more grapes, Berries etc, could be acidic problems.
If you are taking any prescribed or over the counter medications include these. Read the side effects of these meds..