Novices and newbies discussion

I’m still pretty new to this setup and have a query regarding the sizing of the rings. My wife locked me in roughly three days ago, and for once she seems relaxed about it and accepting that I’ll be kept locked up—a significant milestone for us. We’ll see how things progress; I am doing my best to demonstrate that this arrangement benefits her too. Everything is looking good so far.

My main question concerns ring sizes. I chose to go down one size (I wear a CB6000s) compared to what I typically use. The only issue right now is some chafing when I get an erection at night, which brings a slight burning feeling under the ring. I realize this happens because of the movement and pressure, but I’m unsure whether going bigger or smaller would be better? How exactly does ring sizing affect comfort? Is a tighter fit more comfortable? The one thing I have noticed is that if it’s too small, it can restrict blood flow enough to turn things blue(!), which hasn’t occurred yet and is something I want to avoid at all costs. Any advice on handling the burning or chafing during nighttime erections?