My boy had the same thing at about a year old. The same glands you describe swelled until he looked like he had Frankenstein bolts on each side of his face. I freaked out, assuming lymphoma and all the other horrible things, and took him to his vet, who said it's a sign of a healthy immune system responding to a minor virus (he had had the sniffles a week or so before). It took a week or so for them to return to normal.
OH MY, he's had these soft lumps since a pup, wouldn't lymphoma have killed him by now?
We see another Vet tomorrow.
Now I am really worried.
If I was worried, reassurances of an anonymous forum would not comfort me. I would want the opinion of a specialist because enlarged lymph nodes can indicate a serious problem. So I hope you seek the opinion of someone more than a little general knowledgeable about enlarged lymph nodes.
I discovered the same thing on the right side of my dog's face when he was about five months old. Two vets didn't think it was anything to worry about but we kept an eye on it. Finally, I insisted on a needle aspirate biopsy for my own peace of mind. The results came back as an over-reactive lymph node - something fairly common according to the pathologist. My pup's now two years old and although I can still see the lymph node, it has never swelled up again like it had.