I just got a new puppy yesterday afternoon. He's 8 weeks old, and came from a farm. We brought him home, and the whole time he was breathing weird, like he's grunting. He slept throughout the night OK, but when I got up and took him outside, he peed but was whimpering the whole time. (I think that was because it was raining and thundering.)

The not pooping thing doesn't bother me much - we've only had him 12 hours so far. But the grunting, fast breathing does concern me. Should I be worried? Or is it just stress of a new home?