Why is it after i cry my eyes feel dry?

Altered surface: The ocular surface has a coating of mucous that is part of the tear film. Crying reduces this. The eye will feel dry until the eye re-creates the mucous layer.

Dryness after crying: My educated guess is that crying can cause an ocular(eye) irritation which causes a grittiness or redness that may feel like they are dry but are not. Crying does not present for evaluation of tearing or eye dryness. I hope this made sense to you. If you still have questions about it, i will do some more investigating. Hope this helped!