Jnick - first welcome to the site, you're in the right place.
You are extremely early right now. I had the same issues for a bit. Everyone is different, but we were all in the same situation as you're in at the beginning.
As Chuck mentioned, this is major surgery. Some recover more quickly than others, but we are still talking months to a year. So be patient with this, be diligent with your exercises and all, but also realize that you're healing.
Not muscular healing, bone and implant healing in the beginning. It's not like pulling a muscle or any other type of athletic healing. The first six months in general are the time to be conservative.
We are all active in some way here, some athletically, others with demanding jobs. The main emphasis here is in healing within the first year. Some folks can go back to less demanding activities earlier, some have leaped ahead of others, but the bone healing is not something you want to rush.
So at one week, you sound like you're exactly where you should be.
Are you doing physical therapy, or did your surgeon suggest other types of exercises?