Dear P.,
My pediatrician told me when I first started taking my daughter to the doctor as an infant that a high spiked fever (101 or higher) was likely a virus and that the fever shouldn't last more than a few days but other symptoms might last 10 days to 2 weeks. He also said a low, continuous fever that lasted for more than a couple days was likely a bacterial infection that would require an antibiotic to clear up. My daughter is now 4 years old and I have consistently found this to be the case.
Also, anything viral that lasts more than two weeks did turn out to need antibiotics to clear up having turned into something bacterial. Anything that lasted less than two weeks went away without medication.
I agree completely with the other moms here - get another doctor. Trust your instincts!
Good luck and God Bless. E.