Hi Wolf, I have had dozens of these, including one that has progressed into my bladder. Some people are just more susceptible to them than other, sometimes its a structural thing as in my case. Anyways I can give you some good advice here because I treat them naturally and have learned to prevent them entirely. Just so you understand whats happening... The strain of bacteria that causes the infection have hooks on their outer membrane that allows them to gradually climb their way up towards the bladder and irritate the cells as they pass. Here is what I do and have been recommended to do by an ND.

Parsley Tea - steep a few tablespoons in a tea pot and drink, and drink as much as you can. Keep making new batches. Alternate with parsley tea and regular water. Parsley is far more effective than cranberry, it works by disrupting the bacteria membrane and they can't continue to climb. The extra water helps to continually knock them down and flush'em out. I would do this frequently until symptoms are completely gone and then I would have a few cups a day for up to a week just to be sure. Parsley is also natures multivitamin so in general your nourishing your body intensely as well.

Cranberry is good, look in the frozen section if you can't find them fresh - you can juice them and add water so it's not as intensely bitter. But like I said it isn't AS effective.

If you want prevention suggestions you can message me, but this is your first one so I wouldn't worry as much about prevention unless you get another or it comes back.