BLUE TONGUE SKINKS

So i've had my BTS Northern male for about 2 months and i've recently upgraded him into a 40 gallon terrarium but i've noticed now when i him which a lot more often sense he has gotten the bigger room. he doesnt flick his tongue out as often anymore and he breath like in a panic when im around right now. I moved him in about a week? is it normal for BTS northern to do?

Set up
40 gal Terrarium
Bedding Snake Aspen (Breeder had him on it)
Fed daily: Blue brand wet dog food with peas and sometimes fruit added in it i swap out the peas with greens and the meat flavor so he doesnt get bored O i add calcium in too
Lighting is a 75 watt inferred red bulb and a 75 watt basking heat bulb i swap the too between night and day.
2 hides one on that basking spot (where he normal is) One on the cold side
1 water bowl

Maybe you could post a picture of your setup? It sounds fine, personally I would not use aspen but that is a personal choice. I found it to be too dry even for my Northerns. He is more than likely still adjusting to his new surroundings.

what sub do you use? idk any other good ones that i trust around here

I use coco husk, repti bark, cypress mulch or similar.

what ratio of of each do you use? i own a butt load of frogs so i got coco fiber and coco husk out woopie doo so i could swap the sub if it works better i had on aspen because the breeder did but its ugly