Pick up some grapefruit seed extract. It's anti microbial, viral, fungal etc. so it's good for infections. I used it for a yeast infection. I recommend the capsules over the liquid form as it tastes pretty disgusting. Two high doses (maybe 250mg) per day and you should be okay within a day or two. Probiotics would be good to take too. Even your bladder has bacteria in it, and NEEDS it.
I haven't heard of this D-mannose stuff, but Mercola's site shows that it has probiotics and cranberry extract. I think you could probably get cranberry extract in capsule form too, which would help avoid the excess fructose.