how long did your UTI last?

I was taking Augmentin for a little over a week as per doctors orders. I got relief from symptoms within a couple of days and I really thought I was getting better. I finished off the course of Augmentin four days ago but yesterday the burning during urination came back. Then last night I started to get really bad lower back pain and some abdominal pain. They pain hasn't let up since and the burning is still there. Friday made two weeks since the symptoms first set in. Is this normal?