It does hurt but the whole labour process is instinctive, early on it feels like bad period pain but only for short intervals. Later contractions are painful and feel overwhelming but they have a purpose. I felt a distinct change when a had the urge to push and no longer felt any pain just felt like a was passing a football out of my back passage!!! There is a burning, stinging pain when the babys head is crowning and you may feel it if you tear. However, you don't care because you have your baby.
When my first child was 8 weeks old I developed gastritis, oesophagitis and an infection in my gall bladder, resulting in an operation and all I can say is I would rather go through childbirth again than have that pain again!
I have 2 gorgeous kids, long labours with both but I would do it again and again for them for because the pain of labour doesn't matter at all when you have your baby.
Relax, and enjoy it. It is so worth it.