It is painful! But manageable.
The contractions are like really bad period cramps in the first bit of labour. Then in active labour more intense, like your whole body is cramping. But they surge then stop. Each individual contraction on its own is dealable with, what gets hard is as you get to full dilation they come on thick and fast and you are so tired from dealing with them, you feel you can't go on much more.
For me the contractions at transition became less cramping and more pushy. A bit like the vomiting reflex, except your whole body convulsing, not just stomach. This bit was very intense but actually hurt less than the contractions on their own. Just very odd to feel like your whole body is expelling something!
Crowning is stingy/chinese burn-y, but not as bad as you might imagine. It's so close then, you are full of hormones and off your head with endorphins, adrenaline, tiredness etc. It's not like pushing a baby out of there "stone cold" - you are in a totally different place hormonally by the end of labour. Also, you know you are very nearly there, the contractions aren't as painful, you are dead excited and terrified, just shout/yell through it and it will soon be over! The midwives are shouting encouragement, the room fills with midwives rushing around putting aprons on, there is a real sense of anticipation and drama. Whereas with the contractions its bloomin painful and hard work, but no real sense yet of how much longer to get through. I had a third degree tear and didn't notice it specifically, just a lot of stinging. And my DS shot out in 7 mins, so not the most gentle of second stages!
Then baby is out, and it is the best feeling ever. You are so bloody relieved it is over and you have DONE IT! I spent about 5 mins just saying "thank god thank god thank god hello sweet boy thank god thank god!!"
. No pain, you've got your lovely baby, your DP is crying with pride and relief, you get TEA AND TOAST but best of all you have bloody DONE IT and it is OVER thank god!
Really really really recommend waterbirth. One of the things about labour is that it is just so uncomfy to move around - even going to the loo in early labour is awful, can't quite describe it. But once you are in the water, you can just float off into whatever position works for you, its wonderful. It still hurts and is hard work, but somehow the fact you are in the the water, mobile, and pain free between contractions and soothed by all the lovely water, it helps you mentally to think you can do it. I managed on just G&A and a lot of moo-ing, in the water with DS (DD was an induction previously and I had the full epidural with her).
Also recommend getting your DP to distract your body during contractions as it takes the edge off the pain. My DH poured loads of hot water over my back in the pool during contractions. Really helped - just having another strong sensation to feel in addition to the contractions helped distract my brain and made it easier to manage.
(The day after DS was born and I was in hospital after having tear repaired in theatre, DH had the gall to say he had a sore arm from all the pouring
. He got short shrift, needless to say!)