Too pushy?

It has been exactly one week since I called a future employer and tried to negotiate the salary package. The conversation ended by him stating that he would crunch some numbers and get back to me. Well, a week has come and gone and I haven't heard anything back yet. Is it too soon to call him back and just touch base with him? Or should I be a little more patient and wait to see if he is going to call me back? I really want this job. And, in fact, would take it even if he doesn't agree to my proposal, but I am biting my nails waiting for his response. How would you handle this situation?