I would read "Birth Skills" by Juju Sundins and Sarah Murdoch. It is fabulous and it helps you work with the intense feelings and not be afraid of the 'pain' by using a few different techniques and helping you work with your body and contractions.
I have no pain tolerance at all and I had two beautiful drug free labours using these techniques. DH read it too and it really helped him be an amazing support person - the midwife with us for our two births keep going on at how amazing he was - which he truely was.
Best of luck