I was diag. With UTI and given macrobid. 4 days later, still have fever and feel worse! I finished chemo for ovarian cancer in jan. What to do?

Call your doctor. It could be that your UTI is due to some bacteria resistant to macrobid. But your symptoms of fever and feeling worse may be due to something else. You should call the doctor who prescribed you Macrobid and let him/her know how you are feeling. Or go to the er if you are feeling extremely sick.
Need another antibio. Your UTI is likely resistant to Macrobid and need a different antibiotic. If your WBC is still low meaning less then 1500 from chemotherapy then you should go to the hospital.