 [ Symptoms ] uti a month ago and now i have a kidney infection been on antibiotics for 4 days but pain in back is worse [ Disease ] if the pain is worse on your antibiotics then you need to consult your treating medical provider today you may need a change in your antibiotic therapy based on your urine culture hopefully this was done a stronger antibiotic or further evaluation of your kidney pain perhaps you have a kidney stone your medical provider may order a kidney ultrasound