ha! me too.
I had a good experience 2 years ago, homebirth w/midwife for DS. I wasn't very nervous that time, though DH was terrified. Afterwards he kept saying, "you were so great! you were so great!" ie i didn't do the things he was afraid of - scream in pain, yell at him, bleed a lot.
Well... I think this time I'm nervous because, like MamaLori says, I KNOW more gut-level that it's going to be hard. And also because at the back of my mind I think, "well, I pullled it off once, it went great, but can I do it again?" I have higher expectations for myself and the birth this time, because I know how good it can be. Or something like that.