Right Now I'm 18 and For My Bladder infections I've always treated them with Vinegar. What you do is get a tall clear glass and pour some vinegar into the bottom (little) and then fill glass with tap water filtered water. This is what I do so drink it down and drink a few glasses of water, wait till your bladder feels about halfway full before urninating cause the vinegar needs to be given enough time to work. When you go to the bathroom it should not hurt all. That's the cure for preventation.
First: don't take baths the water could be dirty and can somehow end up in your bladder 2nd: Wash good while showering penis needs to be washed good as well when showering.
I have Found out From my Extremely Smart parents that stuff like Soda Pop can cause Bladder infections. The cure, and this is the only cure i did, was using plain White vinegar. Turns out it gets rid of it fast but if you get the Infection in the Afternoon and was very painful I strongly recommend that you drink fresh cold filtered water for the rest of the entire day. It will do you good big time.