Having had a 42 hr labour and a 4 hr one, I had a few thoughts. Firstly - the longer labour started gradually, gave me lots opportunity to get into coping techniques but the duration caused me a lot of concern which did not help with the pain control much. I used every kind of non-interventional pain relief going - visualisation, G&A, TENS, movement.
The second, much shorter labour, was so quick that I did not have time to establish coping techniques that I used before. However I can honestly say I was so excited by how well things were going and how quickly things were progressing that I did not feel pain. Yes, a lot of discomfort and strange sensations, as you might expect, but not pain. I recall sitting on a birth stool waiting for it to start REALLY hurting as I expected it to, and it never did!
What I am trying to say is that the mind is a very powerful thing, and if you are nervous, worried, tense and expecting the worst, then it could well have a negative effect on your body. If you are excited, looking forward to the birth of your baby, feeling confident, etc, it can all be much better.
Why not try to find classes which deal with your mental preparation? I personally didn't get on with Hypnobirthing but I know it works wonders for a lot of people. I also had a one-to-one active birth session with a private midwife that was excellent - I know she does some of these sessions at various birth preparation groups in our area - there may be someone who does similar classes in your area. The power of the mind is usually underestimated - it is a very powerful thing if you learn to use it effectively.
As has been mentioned, G&A needs to be used in a particular way and you should be taught how to make the most effective use of it before you are given it. Used badly it can make you feel very light-headed and have no pain relief at all. Also, induced labours can be worse than spontaneous labours as you are anticipating things and the contractions are artificially stronger sooner.
You are doing the right things by addressing the issues before you go into labour, but please don't try to dwell on them too much with a negative outlook. And, tongue firmly in cheek here, fast labours only seem to be feared by people who have never been in labour for days! I know which one of mine I would rather go through again!