[ Dogs ] Open Question : Why is my Pembroke Welsh corgi kind of different?

Hey, I got a dog about a year ago and I didn't bother to do research on what it it was until now. After extensive searching online, I found Pembroke welsh corgi was a good hit. The only thing is Pembroke welsh corgis are stout and their back is orange-brown. My dog's head is orange-brown, but his body/back isn't. Also, he isn't stout like the pictures I see online, although this isn't too important. Can anyone explain? Thanks a million =D