dear user i would like to tell you that these pus cells in your urine analysis indiacte that you have urinary tract infection caused by bacterial infection............. first we should detect the causative organism for that...........the causative micro organism......as you begin your treatment you should complete the course then doing urine analysis will indicate if infection eradicated or not........if bacterial infection had resistance to antibiotic you are taking and the infection persist suspected treatment should be with antibiotic that bacteria is sensitive to it.........to have best results we should do antibiotic sensitivity test as this test will detect the most antibiotic that bacteria is sensitive for.........as some bacteria causing urinary tract infection may have resistance to more than one type of antibiotics..........to be feverish not astrange point to worry about it now as you are detected to have bacterial infection that cause fever.........your pelvic pain and lower back pain is due to the same cause...........if you have no improvement discuss with your doctor to do urine culture and antibiotic sensitivity test........as to have the appropiate treatment............finally you should know that having pus cells in urine is not adengerous alert but you should follow approbiate treatment ............you can follow these simple steps and you will be fine.....................wish you healthy life