Two things that have helped me in my desire to take more during impact play as a bottom had been learning/ remembering to take deep breaths along with my normal moans/ sounds (so finding a breathing pattern that works for you might help you) and also learning to “let go”/ relax mid mind and muscles and just the the pain happen. This has definitely allowed me to take a greater intensity as a bottom than before, which has lead to greater enjoyment/ release for me during impact scenes.
Your experience may vary, but I just thought Id share mine.
Oh, also don’t beat yourself up if you sometimes can’t handle the normal intensity you two play at. I’ve found that some days or when I get tired my pain tolerance gets much lower than normal and I know many other people experience this as well.