question: About 3 months ago I had a bad toothache (my left side back tooth) I went to the dentist because I.wanted them to pull it but they wanted to do a root canal and then cap it. I did not have the money for all of that so they gave me antibiotics and pain medicine. I finished the antibiotics and my tooth quit hurting so I never went back to the dentist. About 3 weeks later I got a knot right below my jaw line it's about the size of a quarter and is very sensitive to touch. Is this an infection or something else?