How does her lower abdomen feel? Is it swollen or spongey or tight like a drum? She seems to be breathing a little heavy. Will she eat some chopped egg, or take any feed or water? If she is not laying, I would tend to lean more toward internal laying as a possibility. But make sure that her crop is emptying overnight, and not hard or puffy. If you can get some droppings checked by a bet for worms or coccidiosis, that could rule out parasites.