Adopted 5 month old Blue..lots of problems.

About two weeks ago my husband and i adopted a 5 month old Blue pit named Daisy. We figured she would make a great playmate for my other puppy Kilo who is 8 months old. She was just fine before we brought her home. Very excited to see people pretty much. Its been 2 weeks since that day and we have had so many problems!! She wont use to bathroom outside.. she just kinda sits there, or walks around Not peeing or pooping. She doesnt like to listen. She ignores anything we say to her like, asking her to go outside, or even trying to play.. She just sits or lays there, staring at the floor, or staring at the wall. Im very frustrated at this point. I understand she is a stubborn dog, but somethings gotta give!! Any advice???