Pain in penis and pelvis

I've had UTI's or pain when urinating once every 1-2 years for most of my adult life. When it was a UTI, my Doctor prescribed an antibiotic. 5 years ago I was diagnosed with colorectal cancer and went through treatment (2 rounds of chemo, and radiation M-F for about 8 weeks). No surgery. All the bloodwork and tests have shown that I've been cleared. In the last 18 months, I have passed blood twice when urinating. I had more bloodwork done and even a cystoscopy, and both didn't show anything. My colorectal Doctor and Urologist have both said it's still the after effect of radiation. And even called it "the gift that keeps on giving". Every few months, I feel pain in my penis after I urinate and all around my pelvis. And this lasts a few days. My Urologist has since sent me to physical therapy to control the pain.

The reason why I'm posting here is because in the last two weeks, it suddenly feels like I have to urinate during sex. And I start to lose part of my erection. And when I ejaculate, it doesn't feel the same. My penis is even more sore for several minutes afterwards. I plan on discussing this with my doctors but wanted to ask if anyone else has experienced anything like this. Thanks in advance.