I'm on nitrofurantoin for a bladder infection since wed and am not getting better. i have severe lower back pain, nausea, vomited once, frequent urination without bladder sensitivity, headaches, full body pain/sensitivity/tenderness, tingling in my feet a

Kidney infection: It's now Sunday which is at least 4 days later so you may not be taking correct antibiotic for your bladder infection. Tell your treating physician about your continued symptoms. Ask for culture & sensitivity to guide antibiotic choice. Perhaps your bladder infection has spread to kidneys b/c back pain, nausea & vomiting. And get headache checked out b/c nausea/vomiting, tingling, etc.

Consider the ER: if nitrofurantoin were going to work for you, I would think that you should have some improvement by now. It may be that the bacteria causing your UTI are not sensitive to that antibiotic. If your lower back pain is that severe, I would consider calling your doctor or going to the emergency room. Good luck.