My Twenty Month Old Has Been Throwing Up Off And

my twenty month old has been throwing up off and on for two weeks now. She has had diarrhea as well. It has been real thick brown and methane smelling, it has been running brown, it has been green, and now it is cottage cheesy looking. She throws up everytime she eats..this has been going on for almost two weeks solid. She has just a little nasal drip, but nothing concerning, and nothing really that is out of the norm for her. She isn't running a fever. She is super fussy. Her bottom is super raw. She is still trying to do activities with her normal sport, but I can tell she is fatigued and stressed......Our doctor's office wants to see her again, but it will be a few days before they can see her. What is the cottage cheesy diarrhea? Should we be concerned? She is taking medicine for the nausea and diarrhea and vomiting.