I adopted a 6 year old Golden Retriever, whilst still having two 13-year-old cats! The dog, although 6, still behaves like a pup - full of life and fun - and the cats are very set in their ways, having had the run of the house for 13 years! Neither the dog or the cats were impressed with each other for a while, and it took a good couple of months before they all accepted the change. I didn't do anything in particular to help the situation, I just left them to sort themselves out, although I did make sure they had separate eating areas. And now, it's the cats who have the upper hand, because the dog won't go anywhere if there's a cat in her way! But I think, if you give it time, they'll all get on in the end. A week is not long for your cats to get accustomed to this noisy bundle of fun that has just invaded their space. I hope things work out for you! :-)