I have smaller, lighter weight chameleons, so maybe it's just my perception, but he looks a bit "puffy" to me...like there might be an edema issue. I don't know.
A vet visit might be in order just to make sure there are no other issues. I can say that when I've had chameleons routinely grabbing their own limbs, it wasn't a good thing. If it happens rarely, it's probably not a concern, but if it's happening enough the owner is making note of it, it's suggestive of a deeper problem, possibly even MBD.