If it's any consolation, you're not alone on long subsequent births. My first lasted from Wednesday night to Sunday morning. My 2nd lasted more than 24 hours and had to be augmented with Pit. (I waited as long as I could before this happened, but since my midwives work in a hospital, they, too are under a time clock.) My 3rd lasted longer than I thought a 3rd birth would, not an unbearable amount of time, but still.
I have really long early labors. The contractions are not necessarily awful, I can totally deal with them, and very short transition and pushing phases. (Thankfully.)
Mine aren't getting longer, but they're not getting much shorter either. :-)