Young Coastal Rosy Boa, sunken eyes won't eat?

My husband and I got a young rosy boa a few days ago. He's about a foot long and about dime- size in diameter. He's well mannered and friendly but his eyes are TERRIBLY sunken in. I've checked for mites by soaking him in luke-warm water, and visually I can't see anything. When we placed him in his habitat, he immediately lapped up a little water, so he could just have been dehydrated. I'm also concerned since we have not gotten him to eat nor has he defecated...

Is he simply stressed out? Or could there be another underlying problem?

We have him in a 10 gallon terrarium with a 65watt red bulb, calcium fortified sand, a few rock cave hideouts (which he loves!), a bit of indigenous shrubs, and of course a water dish I've been changing daily.

I've had leopard geckos and have a Sulcata tortoise but I'm just not familiar with snakes...

Thanks for any and all advice!!

Pics of the snake would be of help.
A 65 watt bulb on a 10 gallon tank is a lot...what temperatures are you getting with that combo?
Were the eyes "sunken" when you received the snake? Or has that happened since you got it?
If it appears dehydrated - check all aspects of your husbandry. Ordinarily, I would recommend daily soaks for a dehydrated snake; but, I have only a cursory knowledge of rosy boas, so I'll let others more familiar with their care guide you on that.

I'd also switch your substrate and leave him alone for the next week. Dehydration is a possibility and moving is always stressful on reptiles. I usually give them about a week to get use to the new environment before I try feeding.

Lose the bulb...use only belly heat.
Pics would help...
How's he been doing since your original post?