I have what are called aggressive labours, so there was no run up to it where your endorphins build gradually to counteract pain. There's literally no mistaking labour has started as you go straight into fast and frequent massive contractions which immobilise you completely. No talking!
However, I wouldn't call it 'horrific', but I did vote yabu because I dont think anyone can legitimately say labour cant be THAT bad because I thinknit can be.
Although mine are aggressive, I would just call them intense and hard work. My mind was wholly focussed on labouring, nothing else.
All pain leaves once pushing starts, and the crowing feels like chinese burns (which I practiced to help myself prepare!).
Its in and out of pain aswell. So a 20 hour labour is not 20 hours of pain, just intermittent pain, and even then it rises for a count of 10, to a peak and subsides.
For me, contractions would leave me uncontrollably shaking after, or between them, but that was down to the intensity not the pain.
I did recognise the white hot description of searing back pain in a back to back labour.
The worst bit for me was the rip at the end 
I also avoided stitching and was always straight back up on my feet feeling on top of the world.
You hear the worst stories, all the regular ones seem a bit humdrum and dont get talked about so much I guess.
Best bit, and I get excited for labour, meeting baby!!
Disclaimer: probably forgotten a lot!
The fear pp mentioned, yes, get great staff around you to lean on.
OP due now, hoping for her thoughts on it and hoping its gone well for both. 