Bill, your K64 looks normal to me. Your highlights do not seem blown up, and the shadows can only be dark as they are, given the nature of the scene ; it could have used maybe a half stop more of exposure, but not much more.
I've always found that that film had a bit more "70's brown" in its palette than modern E6 emulsions. You won't get the same type of saturation you get with those films, so your shadows may become darker more quickly, and the lower saturation/deep shadow makes the overall contrast less intense to the eye. Pictures taken with it always look a bit as if they are coming from a 1974 magazine.