Please don't let yourself be scared by other people's birth stories. Do your research so you can make informed decisions, but as birthday approaches, stick your fingers in your ears and go "la la la". OK well maybe not, but it's really not going to help your positive frame of mind (or encourage your positive outcome).
You don't "have" to have any medical intervention, it is your choice to make, but clearly with that choice you need to be responsible for understanding what you are deciding on.
My birth plan says no syntocinon unless with-holding would be harmful to mother or baby. That is to say that I will not be induced if my waters break (I am happy to monitor for signs of infection) or if I am less than 43 weeks (will choose monitoring, the risk to baby goes up after 43 weeks, not 42) and "failure to progress" will be taken with a pinch of salt as I am pretty sure my baby hasn't read our local hospital's policy on how long labour should last. I would however accept it if the obstetrician could give me a convincing explanation that in my particular case (not hospital policy "just in case") it was necessary for a healthy outcome.
Of course this is my decision and I wouldn't "encourage" anyone else to do the same without doing their homework first. If you go against policy, you need to know why, and what the benefits and risks are.
Active birth and being relaxed should help reduce the risk that your labour will slow down. Any safe/approved outside help in the form of reflexology, yoga, aromatherapy, raspberry leaf tea, acupuncture or curry can't really go amiss either.