Welcome to Just Answer.
From what you describe it is not the position of a lymph node The submental lymph node would be directly the chin bone while the pretracheal lymph node would be below adam's apple.
It is actually impossible to diagnose this without actually seeing it. I would however urge you to see your GP because no lump should ever be ignored.
I am so sorry I cannot be of much help to you.
With my very best wishes