This sounds like the same gland i guess it would be, that i have a problem with sometimes. one night it just all of a sudden became swollen to maybe the size of a bouncy ball i would say. there was no pain at all. and it later went down. and now every once in a great while , usually if i eat , it swells up sometimes.
I have no idea what it could be , i only just started to look it up a little tonight and found this post. this is the first example i have found so far of someone having the same problem.

It sounds like a swollen parotid gland. The largest of the salivary glands. Maybe you had a temporary blockage of the gland.

The first time i noticed, I was at a restaurant and noticed in the mirror the gland on the left side of my face under ear was swollen and very noticeable. this had never happened before and made me nervous but when i got home it had completely disappeared. every once in a while it would swell up and go away minutes later till the last week i noticed it has been swelling up as soon as i eat and then goes away minutes after i stop. i have no idea what this is caused by but there is and never has been any pain whatsoever associated with it. Does this description come close to the same thing you have been experiencing? if you find anything out about what may cause this please forward any information along to me. thank you

Sometimes focusing on what is wrong , although logical, is not the best way to go...
If you just say 'thank you for my healing' you're sending a msg to your subconscious mind that you want to heal and find a solution. Soon a solution will come. No one needs a diagnosis or a label of their problem for the problem to be solved/healed. Good luck