Your avatar is a pic of the male when you first posted, correct? And I believe you also got a pic of the little lady before you picked them up?
I've not heard of puppies loosing their white fur unless very minimal. The amount of white on his back paw in the avatar is significant enough that it should still be there. Also check the configuration of the white on his chest. (I'm looking at the avatar) There is a definite pattern. One side travels down to a long point. Is this the same now?
I don't want to breeder bash, but could be someone else wanted the cutie with the white foot or none at all. Could be breeder just forgot and knew you wanted a male and female. Still not good business practice.
A friend of mine bred and sold 8 springer pups. As soon as deposit was put down, she tied a different colored yarn bow around the pup's neck and made a notation on the paperwork of what color collar went with which new parent.
As you mentioned, I'm sure you're in love already. It's a newf pup, how could you not. But it must be a bit disappointing if you did not get the pups you picked out and I'm sure paid a handsome amount of money for.