I have three yorkies and their all different. When I got my little boy last year he seemed to like my other dogs better than me. Now he is the biggest cuddler and doesn't leave my side! I'm sure your little one just needs time to adjust. There is so many new things in her life right now I would wait before putting a collar on her. I didn't put a collar on my three until they were a little older. Be patience and soon she will be your best buddy
Hope to see pictures soon and Congratulations on your new furbaby.