C.T.
Sounds to me like she needs rest. When I am sick if I try to bounce back the next day after my fever is over it just makes me feel bad again. She needs to take it easy for the next week. I would guess that she is run down and now she has caught something else and her body is fighting it off. If she tested negative for strep then it is something else. Antibiotics might not do anything you know...only if the fever is caused by a bacterial infection. But she may now have a fever due to a virus (which antibiotics do nothing for)...such as one of the many flu strains or even a milder virus that still can cause a fever. I got the flu last year and it took a whole week of off and on fevers...and then another week of feeling run down and weak.