Celeste,
welcome to the forum. Your work is very nice, including the shots of your Papillon. Very nice.

You may want to work on getting some highlights on the ears/head to pull them off the background. I shoot Rotties and place my lights fairly high to outline the topline/top of head. I also love to use black backdrops so I understand the problems.

Do you use one light or two? Do you use umbrellas or softboxes? I'm fairly conventional in my lighting approach but folks like Julie Poole can give you great advice on how to vary your lighting schemes.

Again welcome and thanks for sharing such nice work.

Jim