BLUE TONGUE SKINKS

I've had him for 3 days and just one question. In the picture where you can see his nose. It's really dark. It wasn't like that when I got him. Is this from burrowing in the substrate or is this a bigger issue like a respiratory infection?

I'm using Repti Bark, and my guys usually get that dark stuff around their nostrils and in the spaces between scales. So unless you see discharge or hear weird noices I wouldn't be worried.
But since you've only had him for a few days it can be daunting to try to distinguish between the different noices they make. Sneezing is perfectly normal. So is exhaling loudly; huffing. Hearing sound when they breathe in is more of a reason to worry.

Hope that helps.
I've only had BTSs for a little over a year and have been worried myself about their seemingly erratic breathing.
Read the Caresheet carefully through, and if you still have questions there are, thankfully, lots of experienced people who can give you excellent advice.

Hi, welcome to the site! Yoshi is a cutie-pie.

Yoshie looks good.

Thanks guys and you nailed it right on the head. I'm using repti-bark. and he seems to love burrowing. He's settling in quite nicely. Doesn't seem to spoke as easily and even walked towards me while i was changing his water tonight.

Welcome!!

Anyone want to take a guess on what Breed Yoshi is?

He is Merauke.

What Susann said regarding ID and the breathing. Breathing sounds normal, just watch for any discharge from nostrils / eyes. If no discharge, a big of huffing or heavy breathing is just fine.