I agree. The nurse could have used a more tactful approach, but if there was something that alarmed them, they'd be getting you in directly.
I've had results that required me to go back in to see my doctor after labs. Whatever it was, we discussed it and addressed it.
I would think the point was just that they want to make sure, while this is all fresh, that they get stepping.
Try not to worry, and know that everything is taken care of: The lab work done, the phone calls made, and your appointment scheduled. So that's great. You're right on top of everything!