I had (have) this problem. It constantly felt as if I was coming down with a bladder infection -- urgency, burning and all the other symptoms except fever and chills.
Turns out the problem for me was caused by milk products. By avoiding milk in all forms, I'm okay. One little smidge of cheese or a single sip and the symptoms start. Milk is often hidden. Turns out whey, which is the clear-ish liquid part of milk, is added to many foods these days, especially baked goods. If I don't read labels closely I'll be feeling uncomfortable soon.
From what I've read, milk is a frequent culprit if a person has a tendency toward bladder irritation. It didn't start bothering me until I hit somewhere around age 30. No idea what triggered it ... except maybe I O.D.ed on milk by consuming so much over so many years.
It would be worth looking at milk and other food triggers. I love milk in all forms and it was hard to give it up, but I strongly prefer to not feel my bladder every minute of the day. It was almost impossible to believe that something so bland could cause such irritation.
Here's a list of bladder irritants from Johns Hopkins. Milk is the only food on the list that bothers me.
http://www.hopkinsmedicine.org/johns..._irritants.pdf