Hi Y.,
I think that labor is a scary thing, no matter what, so the closer it gets to more nervous you get and it's normal, and when you think there is something not "normal" more so.
I would talk to the doctor, tell your concerns and make a clear statement that you do not want to put ANY strain in you or the baby and that you are not closed to any birth method, being either a natural or a C-section.
I imagine that you trust your doctor's judgement, so just make clear that you do not want your baby to suffer any risk... some doctors thinking that natural birth is the best option (and it is but not for every case) wait too long in labor to perform a C-section.
I had two c-sections, the first one after more than 14 hours of labor, I just couldn't dilate enough and by that time my baby was suffering too much, by the time the doctor decided to perform the C-section it was an emergency, and even I think that natural birth is better I wish it would not have gotten to that point. It just added to the fear of it all (it was not my doctor but the doctor in turn) and my baby had to spend the whole night in intensive care unit for "observation".... but he is fine and healthy.
My second time around was c-section from the begining and for that reason was much less stressful. I knew what to expect and the timings.
By the way, personal choice but I HIGHLY recommend the epidural.
Here is a website that may help you easy your concerns, type labor and delivery at their search.
babycenter.com
GOOD LUCK, AND CONGRATULATIONS!!!
M.