Hi I just wanted to fill you all in! I spoke with my doctor, and the swelling was due to a stone in my salivary gland duct... I think it is a side effect of radiation, but nothing serious. I noticed it when I was eating, which is when your mouth secretes more saliva, and the stone caused a blockage, causing it to swell. I massaged it down though and it went away! So, if this happens to any of you, don't worry!