i think you need to get her examined by her doctor as you mentioned that she is crying and puking out things.
it could be that she has picked up some infection and this is making it difficult for her body to digest anything. not getting her treated now will eventually lead to dehydration, as she is vomiting. please try and give her some homemade ORS, by making a mix of a pinch of salt and a tsp of sugar in a glass of water. give her this at an hour's interval through the day, as much as she can have, and also take her to the doc.
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