What Causes Nausea, Swollen Head Feeling With Pain And Vomiting?

hi, my daughter is 14 and she is running fever nausea vomited one time has a stopped up nose she says her head feels swollen she is complanning of pain in her head and neck that shoots down into her knee she also sounds very congested when she sleeps and same syptoms two weeks ago took her to er they gave her antibotics but she didnt get copetely well i dont think and these symptoms are back what could it be do i need to take her back to the er.