What Causes Vomiting And Fever After Removing Adenoid In Child?

Hi um my 3 year old had her adnoids out ton the 3rd well now she is sick she threw up 3x starday 2x sun and 1x yesterday witch was Monday and 2x today I took her to her Dr she couldn't figure out what's going on she has a nasty smell to her as well like a sulfur smell that is constant not only when vomiting and she has had a fever up to 102 her Dr sent her home told me to just push drinks but she won't eat at all and geting her to drink is soo hard I'm worried and Idk what to do