Is there something wrong here?!

Is there something wrong here?

This afternoon as I was driving home, I noticed a sore on the inside of my gum on the top left side. It was about as large as a molar, and sort of hurt, but didn't really. It was squishy, like a blister.

I hadn't noticed it when I brushed my teeth in the morning, or during any of the day's earlier activities. And after I ate a sandwich, I noticed that it had popped, and felt a bit raw. Now I think there is another blister forming.

Is this something I should be worried about? I'm pretty young, and do not drink or smoke, so I really doubt that it would be oral cancer. It could not possibly be an STD. I didn't burn my mouth, or eat something that I'm allergic to. So, could it be gingivitis or a cavity of the gums or something?

I've seen my dentist pretty recently... about four and a half months ago, I think. But should I make an appointment, or am I worried about nothing?

Hey that's too bad to hear about what's going on. I would definately reccommend seeing your dentist just to make sure it's nothing "too serious." I have one thing in mind that it could be, herpangina. Either way, I would suggest drinking a lot of fluids, staying away from salty foods, avoid irratating, salty foods, and seeing your dentist as soon as possible just to make sure.