Sugar Sensitivity when I eat certain foods...?

Ok I'm a college student who is having a small problem. It only happens when I eat gummy things, gum, sweedish fish, gummy worms, twizzlers ect. My teeth begin to hurt when I began to eat them. Orginally it was only my back teeth, when I told my dentist she told me it was probably a cavity forming in between my gums since I tend to forget that area when I'm flossing and it would go away if I flossed. Well it's not, it's now spreed into my canine teeth, which I hit everyday with my flossing. The weird part is that it only happens when I eat gummy foods. I can eat a sugar filled cookie, a Jones Soda, but gummy foods and the occasional chocolate set it off. Can anyone help me out, since I won't be able to see my dentist till thanksgiving?