Keep yourself very busy Katy - do nice, relaxing, enjoyable and/or personally-challenging things you wouldn't normally do if she was around. Then next time, you'll associate her going away with treats for you!
Have a hug. IT's a biggie but she will cope and learn some useful skills on the way ( regardless of the course!). You will learn skills too- a little trial in how to adapt to having her a little further away from you, but she'll still be your chick and you'll both be happy to have her under your wing at the end of the week.
My kids are adults. DS (20) lives a long way from me but I still worry about him. Not in a way that means I interfere but in a natural, loving way. I think it is our place to worry, worrying doesn't mean you are a 'wuss', it means you love her.