That was one thing about my sessions...I never had any pain. I, too, had a Lupron shot before the sessions. That cuts down on the testosterone production so that the cancer has a lesser chance of growing. It was for 6 months, although it's side effects can last up to a year or so. Time will tell as to whether they will prescribe another shot. I had more hot flashes with it in the beginning, but it has slowed to just a few each day now....that was first given in early October 2019.
The SpaceOar makes a huge difference, too, in the rectum area of potential problems. That was offered to me when we were first looking at Proton treatment----but, not when it had to change course to Photon instead, due to my insurance not yet covering Proton treatments. However, having learned all that I had about the SpaceOar, I definitely wanted that and requested it. My oncologist was fine with that, and my insurance did cover that part.