Lab Puppy- breathing heavy in sleep?

We got a new black lab puppy today. Today is my first night with her. She's about 6 1/2 weeks old. She's breathing heavily in her sleep what should I do? Its not a rhythmic breath eather like shell breathe heavy forle then shell stop and then suddenly she'll start breathing heavy again. Oh and by the way she's asleep while doing this. She was fine during the day but just right now is when this is happening.