A few days ago when I was brushing my teeth I noticed a little bit of pain in my left cheek. There is not a visible ulcer, but it did bleed a little last Friday. My cheek is now thicker and the swelling is visible to other people. I also notice that when I brush my teeth the toothbrush doesn't go back there very well. The inside of my cheek is swollen, or thick. I do not know if this has been there and I never noticed until the pain, but it has me very nervous. I know I have a PET scan tomorrow, but I am not sure I trust those.