Thanks Everyone for the advice and support!
I dropped Poppy off this morning and just like Iscot said, it was very hard! She was so excited to go to the vets and raced inside only to be greeted by a fully grown GSD. They both wanted to play so badly but couldn't! Haha!
A friend has lent me a collar she bought for her BC but I'm wondering if its a bit big. Its a medium sized one but I don't know that she will even be able to get through the door of her crate with it on!
What should I expect tonight? Do I let her walk around? Or try and keep her in her crate, taking her out to toilet every few hours? Do I feed her?