I think it is worth saying that it IS painful to be in labour. Yes, different people experience it differently, but by and large, it IS painful.
If you know this in advance it might help you - if you believe the stories about it being a breeze, you might panic when it starts to get really painful. However, as Secondtimelucky just said, you are much stronger than you think, and you will be able to get through it.
At my NCT classes (3 births ago!), they said your perception of pain is dramatically different according to your surroundings, and I think this is true. I didn't need any drugs during my homebirths because I was relaxed, in the warm water, and mentally coping with the pain. I did need drugs the first time I gave birth, in hospital, when I was alone and frightened. (BTW that is my experience, obviously lots of people have relaxing experiences in hospitals too).
It is also worth considering how you'll feel if you need a caesarian. Research that, too.
Actually giving birth is an amazing feeling. I love it! I love seeing my baby for the first time, I loved floating round in my pool afterwards, and having a nice cup of tea made for me. I imagine it must be the same sort of feeling as finishing a marathon (Disclaimer - I have never run a marathon).
Congratulations, whatever your birth story is, it will all be worth it!