My 20 year old daughter had the flu last Sunday through Friday...achy back, low fever, sore throat with thick mucous, coughing and head congestion. She was put on Tamilflu and felt fine by friday, although she didnt take the last 3 pills. She is back at college this week and last night felt nauseous with a burning feeling in her upper, middle stomach area. She has been to the nurse there. They gave her an anti nausea med and peptobismal. She has thrown up 4 times since 8am. And is still experiencing this burning feeling like heartburn in her stomach.