German Short-haired pointer(has mostly liver coloring)
Pointer AKA English Pointer(can be a variety of colors)
The majority of German shorthaire puppies and dogs are all the same color. However, the Pointer can be varied in color and it will explain coloring on the AKC websites. You can also look up more pictures of each breed on the AKC website. Basically, both breeds act a lot alike. They are breed for the same task and have similar energy levels. At 13 weeks, the big difference is going to be the coat and coloring. Hope these links help you figure it out.