I get a kind of soreness/discomfort and pressure feeling though it's not an infection. I've found that stress and diet are the two things that trigger it. (I had some bad news last month about a family member and again about a friend and within minutes of hearing the news, my bladder started acting up!) Cutting right back on caffeine, spicy or acidic foods (no oranges, gherkins or pickled onions!) helps, as does camomile tea - I drink 3 cups, one after the other, on the first day and then have a cup a day until I'm back to normal.
Camomile can actually cause irritation instead of easing it if you overdo it when things are normal, so I don't usually have more than one mug a day, but with an acute flare up, I find drinking more of it helps.