Hi, The belly spots are refferred to ask stress marks and tend to show up if the beardie is stressed. The dark coloring is usually a sign the dragon is cool and is trying to warm up. Dragons tend to darken up when they are trying to warm up as darker colors absorb more light/heat and once they reach their ideal temperature then will usually lighten up. As for the stress marks some dragons always have them no matter waht some rarely have them as long as your providing the correct environment you should be fine..