Staying near heat lamp?

[Arirang]

Hello, all.

So, I took Norbert on a couple of errands today. Basic, low-stress stuff he's done a million times and seems to enjoy. However, once we got back (going on five hours ago), he's used his climbing background to sit near his heat lamp. He has stayed there, only moving his head. His habitat is plenty warm enough, so he's not cold. Is there something going on that I should be worried about?

While out, he was normal color except for about ten minutes in a cooler environment, when he went darker. He was perky, active, curious, etc. both before and during the outing. We weren't out that long, and except for that ten to twenty minute period early in the outing, it was quite warm. We did use his new harness, but after about five minutes of struggling, he acclimated very well to it.

He has now opened his mouth while hanging on his wall. It may have been a yawn as it closed soon after, but I know how they use this to regulate their temperature. It just seemed really weird and he hasn't done this except when it was too cold.

I use a ZooMed ReptiSun heat lamp and 10.0 UVB (new, functioning). The temperature in the tank is around 105, and Norbert is approximately ten to twelve inches long.

 

[Arirang]

Update: He is very alert and everything, watches my cat and me move around. I did move him as the way he was sitting made it look like he had a massive impaction bulge (he doesn't). I set him down elsewhere and he went back to the same place.

I should also note that it's the closest place he can be to the heat lamp.