My daughter has had unexplained fever for 4 nights now. She ended antiboitcs for sinus/ear infection over a week ago. Not contagious?

Viral = contagious. Routine ear infections usually don't need antibiotics. Neither do most sinus infections. The viruses that cause most upper respiratory infections are contagious. Consider her contagious especially while having fevers. Take her to her doctor to evaluate for the unexplained fever.