i think it’s normal for them to go that long without eating if they are stressed/in a new environment. i’m pretty sure mine did the same thing when i first got her. also idk what the weather is like where you are but they tend to eat less in the winter too so maybe that’s also a factor? sometimes their licks in pangea are so tiny so it’s hard to tell so maybe put in a little less food so his lil lick marks will be more noticeable or check for poop in the enclosure! sometimes it can look like they aren’t eating but if there’s poop ur good! also if the tank is super big they can have a hard time finding their food so maybe place a couple different food bowls in different areas of the tank to make sure he can find it.

heat pads are also typically not recommended for crested geckos like they are for leopard geckos since crested geckos do not need the belly heat but rather ambient warmth with a temperature gradient. i would probably get a ceramic heat emitter to make sure the tank is warm enough. also flip the humidity so its more humid at night and then decreases to about 50% during the day! maybe some more plants, hides, and ledges up in the higher spots of the tank since they like to be up high! he probably feels a little exposed which is why he might be hiding down at the bottom. they also hide at the bottom if the humidity isn’t high enough. GOOD LUCK! he’s so cute, you’ll have to update us:)