I Just Had The Flu Last Wk. Fever Coughing And

I just had the flu last wk. Fever coughing and body aches. Went to the doc and gave me tamiflu. It help little but still had this really bad cough. Then my stomach turn very upset to the point I can't even eat anything. I have no abdominal pain and just eating crackers and lots of water. Could this cough be upsetting my stomach? Been nausea 3 days.