I had those comments too with baby number 1. And since it was so uncommon at the hospital too, to have a natural labor, I got the unbelieving shrugs and the "it's still not too late.... if you change your mind...." from the nurses.
I started doubting myself, because of everyone (except my mom) acting like I was attempting the impossible. So I got a dose of staydol because I let them make me afraid of the pain.
But it turned out that It wasn't more than I could handle after all. The drug sucked and made me sick, and I realized, thinking back on my birth like, "That wasn't so bad, except for the sickness from the drug...." So DD2 was born without any pain-meds at all! Because I knew it wouldn't be so terrible after all, I'd already done it once!
And after you do it once, people (who know) don't say stuff like that anymore. And it's on your "record" after that, so even the nurses don't act like it's impossible. You won't have to deal with it so much again!You can do what ever you believe you can do!
Don't let the personal fears of others affect you! You can do it, because you've decided to do it!