My burning came to my attention about a year after the radiation to my prostate. I voided some blood, had problems with incontinence, and repeated UTIs.

Imaginging (cystoscopy) showed mild radiation cystitis — light burns to the lining in the bottom of my bladder. They're probably permanent. It took a few months to get things under control, but it's only a minor nuisance now.

If lifestyle changes like keeping hydrated and minimising food/drink that irritate you don't end up helping enough, there are other treatments, like filling your bladder with pure oxygen periodically to promote healing. Talk to your urology oncologist about diagnosis and options.

Best of luck.