All clear - maybe

I really, really loathe talking to veterinary specialists. It's like trying to nail Jell-o to a wall. The upshot is: they "appreciate no abnormalities" in Roc's x-ray, see no reason for further testing and generally looked at me as if I were insane when I asked if we shouldn't do the ultrasound our regular vet sent me up there for.
So - what do I do now? The vet who's been taking care of our dogs for a couple of decades, has fantastic diagnostic skills and who's never been wrong thinks something's going on with Roc. And the specialist tells me nothing's going on, since he has no acute symptoms and no obvious abnormalities.
That sound you hear is my head hitting the desk. Repeatedly.