Mouth ulcer or gum swelling?

I'm trying to figure out if this in my mouth is a mouth ulcer/ canker sore or inflammation of crown of my guns on the back. I noticed it Wednesday after eating popcorn Tuesday night. It started off as just peeling and itchiness of the area. It doesn't hurt when I eat or drink anything. It also isn't painful when I gargle with warm salt water Listerine or peroxide. Its only painful when I push it really hard with my tong or use my finger nail to push it down. When I push it with my nail it sends a sharp pain through my tooth like a nerve pain. I cant figure out what this is. I've never seen or heard if anyone getting a canker sore on this location.

2014-11-03 10:58:54

Amy