Annoying mouth sores
Every few months or so, I get these weird annoying sores in my mouth.
They seem to form near the bottom of my gums, where the gum and inside of the cheek/mouth are against each other, they are VERY painful, and they stick around for at least a week.
Back in July I got one on the bottom of my mouth, and in the last week or so I've gotten one on my gum/cheek. It feels like it's FINALLY starting to get better, but these things just drive me nuts.
What would be causing these?