Hi Shazza
Congratulations on your new arrival!
We adopted a 5 yr old GSD cross from a rescue centre many years ago, and I well remember her confusion and distress in the first few days.
Hang in there, keep things in the household routine as much as possible, but, from my experience I would advise not to over-indulge him in love and affection; we found after a few weeks that we had a rescue dog who thought she was Top Dog in our house - entirely our fault for being too soft and not ensuring that she knew her place.
Enjoy your new man - whats his name? I'd love to see a picture in the gallery....
Oh, and welcome to COL!