There's lots of things that can cause a saddle to hurt. My saddle has bothered me off and on all summer. I couldn't figure out why but when you look at my saddles they are compressed on the right side but not the other. My right hip and leg is weaker than the left and according to my bike fit guy its causing me to slide across the saddle. Lately, I haven't been noticing the saddle so much but I'm gaining more strength in my leg.

Also, when you make changes on a bike your body is going to feel it because it has adapted to the old position. It's not going to change overnight. After more than a thousand miles with my narrower handlebars my arms are still fighting the handlebars on longer rides. At first I thought it strange, my body should feel better with the correct size but I've ridden for years with handlebars that are too large, and now I'm expecting my shoulders to adjust to changes overnight overnight.

When I got my new bike my fitter recommended I keep my rides short, 15-20 miles for the 1st week or 2 to let my body adapt to the differences.