People have died from a UTI, just like people have died after a minor cut during a pedicure or a small bump to their head. UTIs are extremely common - millions and millions of cases a year. I have had probably about 10 myself. You take the antibiotics, drink lots, and it goes away. Only in extremely extremely rare cases does a UTI turn into a larger, more deadly infection. I really would not go there in your mind, something so unlikely is not worth the agony and panic.