where do tears come from
Tears come from the lacrimal gland. And it's found in the outer part of the upper eye. When excess tears are produced, they drain into small ducts to the nasal cavity. And if you have too many tears to drain, they'll spill out of your eyes. There's an anatomical reason why crying makes your nose run.
If something gets in your eye and irritates it, your tear glands make more tears to try and flush the irritant away. These are reflex tears. If something makes you sad or extra happy, your tear glands produce emotional tears.