First I'd pay close attention to his behavior patterns (alertness, energy, etc.) and see if they change. Then I'd check his weight, food intake, and make sure his poo looks good (well, good as in not runny or strange).
If he starts losing wieght, stops eating or his poo doesn't look so good I'd see how long this lasts. If it lasts for more than a few days to a week depending on how severe the changes are I might become worried.
Besides all of that I can tell you my beardies have shed at times and it doesn't look the exact same every time. For instance when my hog was smaller most of the shed patches were complete body parts whereas now it seems completely random and even small sections of body parts will shed. Like a small spot on his back. Also, the skin sometimes has not looked the same color as usual which I think is similar to what you're experiencing. Sometimes it is dark and sometimes it is light. Sometimes it seems thicker and sometimes not as thick. Sometimes it sheds quickly and other times it takes forever.
Sorry this is so long. Give it some time and if there are no signs of ill health don't worry about it.
Good luck and I hope this helped!!
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Rob Talkington
