Absolutely! Impaction is a blockage after all. Since he isnt eating much, he shouldnt be pooping much. You MUST take your skink to a qualified herp vet(look in the phone book and call vets to see who do reptiles). A vet will be able to take X-rays of your skink to determine if there is an impaction. I have stated this countless times: IF YOU DONT TAKE YOUR VET TO A SKINK NOW, IT COULD VERY POSSIBLY DIE. Impactions are very serious and if you delay taking the skink to a vet, the situation will worsen, and the impaction will have to be surgically removed. And surgery for any animal (even humans) isn't cheap. So I repeat, take the skink to a vet and have him or her diagnose the problem.