lower urinary tract infection is also known as a bladder infection. the most common symptoms are burning with peeing and having to pee frequently (or wanting to pee) without vaginal discharge or significant pain. these symptoms can vary from mild to severe. in healthy women, the symptoms last an average of six days. some people will have pain above the pubic bone (lower abdomen) or in the lower back. people who have an upper urinary tract infection, or pyelonephritis (a kidney infection), can have flank pain, fever (a high temperature), or nausea and vomiting. those symptoms are in addition to the normal symptoms of a lower urinary tract infection. in rare cases the urine looks bloody or contains visible pyuria (pus in the urine).