I know how you feel. When I was going through my second labor, I started remembering how much it had hurt the first time and I was scared I wouldn't be able to handle it (even though I managed the first time).
But it never got as painful or overwhelming the second time around. And odds are that you also will have a shorter, easier labor this time. Not that it didn't hurt the second time - but it didn't last as long and the contractions never got as close together (I had nonstop contractions at the end of first stage during my first labor, they never got closer than 2 or 3 minutes with my second). The pushing stage was much faster too.
I'd concentrate on practicing relaxation/pain management techniques - I've really liked the book "Natural Childbirth the Bradley Way" by Susan McKutcheon.