If it hurts in the morning before you even deadlifted it sounds like you need this book:
http://www.amazon.com/Healing-Back-P...3956602&sr=8-1
It goes like this:
Today [rest day]: my back is feeling very fine. no pain at all. tomorrow i have to train, and it is deadlifting day...
Tomorrow [training day]: it is morning and i have just woke up. going to the toilet room to wash my face, bend over to wash my face... oh my back!! it is very sore. it begs me not to deadlift today.
It is a very weird phenomenon.
BTW today I learned how to deadlift properly (i think) for the first time. I deadlifted today again and this time didn't injure my back. i do not fear deadlifts anymore now. so my back might not feel sore next week the morning of deadlifting day again.
it is psychological. i know the why. but the how amazes me. how can you feel physical pain from psychological issues? and how do the body knows that i want to deadlift today? and the other hows. that shows mind is a powerful thing. and i shall take the better of it in my advantage instead of letting it be in my disadvantage. i shall master the mind.