What is this hard bump in my mouth?

I have this hard bump on the back of my mouth, I'm scared.
It's between my wisdom teeth and my cheek, I have no idea what it could be. It's not like a pimple or something that can be popped because it's hard. It hurts to chew, and hurts to talk. I tried...

some teeth whitening kit and ever since I tried it this bump appeared.
I'm scared it might be serious and I cant see a dentist till Oct.6th!
What can I do?

When my wisdom tooth gets inflamed if I brushed it too hard or something, I get something like that. I would try to restrict movement to touch it (e.g. playing with it with your tongue, etc), and keep going with some good antibacterial mouth wash..

Did you mean your dentist appointment is on NOV 6th?

well it could just be an irritation to the teeth whitening stuff.. or it couls be a cold sore. rinse your mouth with mouth wash a couple times a day and see what happends.

Ah.. sorry, yes. My appointment is November 6th.

It could also be a reaction to the teeth whitener that you used. Just keep your mouth clean with antibacterial mouth wash or you can make a paste of baking soda and water to put on it (you could also rinse your mouth with this).

Good luck