Should I Call An Ambulance?? I have a kidney stone that is too large to pass on its own.?

I was seen in the ER on 6/16/11. And they sent me home with Lortab and Phenergan. I took both at 11:30, and I'm still nauseated and in pain. The dr said something about not wanting to operate on my kidney, or break up the stones. If I call for an ambulance would the ER do anything different?