Hi, just noticed this dark spot on my baby's chest and I'm freaking out (his legs are dark because he is shedding them right now) he's eating and acting normal (maybe sleeping a little more then usually but nothing drastic). He's in a a 40 gallon breeder, has a basking spot, cool hide and things to climb on. Repti sun heat bulb and tube uvb (installed in the tank). Any insight will help thank you!!