swollen lymph nodes

28F currently on Lamictal 25mg

Started around 1/17 - two painful circular bumps (hard & immovable) on my mastoid process behind my left ear. No internal ear pain, no ear ache, no throat/nose pain/oozing/swelling. No fevers. The P.A looked inside both ears & my throat. No wounds on my upper body. They are tender to the touch, some redness behind the ear. The only thing new for me is starting Lamictal 25mg on 1/5 which I take at bed time and have had no issues with as far as I can tell.

1/21 - went to an urgent care & the P.A said she believes they're lymph nodes, told me management just rotate ice & eat and take ibuprofen.

It's now 1/25- they are still there tender, same appearance & size.

Could this be related to my lamictal? Is it common? Concerning?