I had one done too last month. My grandmother had colon cancer so I had mine done earlier than usual.
They say you are knocked out and won't remember anything. Well, I remember turning a bit and saying something in a moan. You don't feel anything but I do remember it all clearly. I asked the medical staff about it when I woke up. Didn't get a concrete answer from anyone. It seems that you are able to communicate and some people say the wildest things when they are in that state.
Wonder what I said too! I have the feeling that I was cursing a blue streak.
"I often do not start fishing until the cool of the evening..."
Norman Maclean: A River Runs Through It