OUCH!
As we age there is a certain amount of receding of gums which may cause aches and pains. Is there a Dental Hygienist in your Practice who could give your mouth a very good clean? She/he can also show you the correct way of brushing.
Those small Ti-pee brushes, sold in supermarkets, are very good. Pushed though between each tooth it can get rid of a lot of debris. I'm surprised every morning after breakfast how much I remove, I think that most of my nourishment gets left behind between my teeth!
Do check your toothpaste and avoid any with Sodium Laurel Sulphate - if used my mouth burns as soon as foods touch my gums especially bananas or chocolate! Is the pain constant? MayB try a pain relief to give you some rest from it.
Let us know how you get on.
