Last Sunday I noticed it was difficult to chew on left side of mouth... The whole side felt sore.. by Tuesday, I couldn't eat or drink anything and my whole left cheek was swollen. I went to my dentist and he gave me Amoxicillin and pain killers. It's been 5 days of antibiotic and the pain is still present but less server and my cheek is still swollen... But now I have about 20 small ulcers inside my mouth along the upper left teeth and jaw line!!! I called my Dentist office and they are closed today... My mouth is HURTING!!! I have had 3 past root canals to the last 3 teeth of the upper left side... What do I do now???