RED BUMP UNDER TONGUE! CANCER?

I'm 12 years old. This morning, I woke up with a bump under my tongue, near the left side of the little flap. I didn't know how it looked like at all, I just felt it with my tongue. A little while ago, I looked in the mirror and the bump looks like a blood mole. It's entirely red and about as bid as a capital 'O.' What could this be? Should I be worried? I'm getting my mouth cleaned, examined, and braces on tomorrow, but I just want an idea of what the doctor might say.