Hi Ric,
I had some discomfort and urgency for a good few months after LDR BT but I wouldn't have described it as painful, more just annoying.
It may sound obvious but are you keeping fully hydrated before going ro bed? My dad who also had LDR BT was his own worst enemy and thought if he didn't drink as much before bed, he wouldn't have to get up as much - after about 10 years he realised that wasnt true π
Are you taking Tamsulosin? Have you tried taking a couple of ibuprofen before bed?
I'm 100% non medically qualified but for me, if you're doing all of those sorts of things and still have more than 'average' discomfort, I would reach out to your GP - they'll probably want to rule out uti/bladder infection etc and probably give antibiotics as a matter of course. After that, there's other drugs that may help.
Also be aware that you're probably in or at the start of peak symptoms from the radiation. That could last another 12 months but will hopefully subside with time. Despite that though, dont suffer in the hope it will improve, seek proper qualified advice if you have any doubts.