How much does your puppy weigh? If under 10 pounds a meter (3 feet) fall with no obvious signs of injury I would just let pass. As for the Tiredness, I have not experience to explain, but in the absence of any other signs in eating, sleeping, touching, bowl movement and appetite I would likely take no action. Many of us do a regular check up (once a year) with a veterinarian and if that was my practice I would likely move one up to do soon just to get a professional examination and opinion.