My Daughter Awoke At 4am Thurs With Beginning Signs Of

My daughter awoke at 4am Thurs with beginning signs of flu. Went to Dr at 3:00pm. They did strep and influenza swabs and both came back negative. As day progressed, symptoms became worse. Today her fever was 103F which was lowered by acetaminophen/ibuprophin alterations. Should we go back for another influenza swab today, or let it run it's course. Thought maybe we could get some Tamiflu to reduce days of suffering, but maybe we went too early?