What Breed Is My Dog?

I had this dog a year ago. I found her and then gave her to a loving home. I was wondering what kind of dog she is? I thought she was a Chihuahua, but her facial features resemble those of a Pit Bull. She never grew taller than 7 inches on all fours and she weighed 9 lbs. Her paws were also big and heavy. I have other Chihuahuas and they were lighter and their paws were smaller. I lost contact with her new family so any help would be nice.

By Rick R.