For The Past 5 Days I Have Thought I Had

For the past 5 days I have thought I had a uti. I've been taking azo but last night I started to pee alot. And am still peeing like every 10 minutes and a regular flow. I went to the doctor today and he said my urine looked fine and didn't see any infection. It does burn a little bit but it's before I pee. What is the problem?