Oh boy he's really not doing good. Honestly it sounds like he does have one of the two conditions I was thinking of based on what you've described.
He's suffering some form of neurological issue which can either be caused by pretty severe metabolic bone disease, or from adenovirus.
If it's caused my mbd, things can get better. You need to make sure you're lighting is perfect, and the rest of your husbandry is perfect. Having a proper
uvb bulb is crucial for dragons, especially those with MBD.
If it's ADV, unfortunately, in most cases when they are exhibiting symptoms this bad this early, they don't usually make it past 90 days. That's the big reason some are against buying petsmart dragons, they often times have major health issues such as this.
Poor fella, he really does look he's not feeling good at all.
So the best you can do now is upgrade your
uvb bulb to preferably a reptisun 10.0 long tube. Or the Arcadia tubes.
I'd get rid of the heat pad. If hes that lethargic he might overheat himself if he doesn't have the energy to move.
I'd also try to bump your basking SURFACE temp to around 105. Babies like it warmer at the basking site.
And try to feed his as healthy a diet as you can. Continue dusting your feeders once a day. But it's important to have that proper uv so that the calcium can be absorbed better.
Mealworms aren't the best option, but if hes able to digest them fine and he's pooping fine, they can be PART of his diet. Some other options would be crickets, dubia roaches, silkworms, butterworms, and black soldier fly larva.
Good luck to your and the little guy!
-Brandon