Look bro, you probably started off to heavy and did to many reps. What is your weight, most people will feel some discomfort the first time doing deads, especially if they have a very weak back, but it gets easier after awhile. I deadlift 600 lbs and my back never hurts, but hey, been doing deads for 5 years. You should stop crying about the pain and suck it up, ever hear of the saying no pain..no gain. Unlike my back, most of my other bodyparts are always in pain, and I love it. Learn to love it or stay a crouch potato. Deadlifts/squats will make you big, thats good advice....take it.