Insect and Spider Identification: what is this? Tiny black round hardshell bug from dog, 3 by deerhnter77

deerhnter77 wrote:
I live in western Virginia and have a Boykin Spaniel .I crate her overnight and when I let her out this morning, there were approx. 70-80 of these bugs alive and dead in her crate and she had a bald patch in the middle of her back.
The bugs are tiny like chia seeds, round with a hard black shell and what looks like reddish brown legs which are near impossible to see. They move very slowly, don\'t jump or anything like that. It\'s really alarming to see so many in such a localized spot. I squeezed a few between my finger nail and they kind of pop and red blood comes out. (More than I though was possible) these pictures are just a few. Any help is greatly appreciated. Thanks