90 degrees to room temp is a tad cool. Up the wattage of your light bulbs and generate some more heat. Babies need slightly higher basking temps: 100-115 in the basking site and 80-85 ambient. Make sure he is getting some UVB from high quality reptile bulbs (or natural, UNfiltered sunlight). Heating rocks are of doubtful value (and can cause burns).
Dragons need both adequate heat and lighting to stimulate the appetite and adequate heat to digest. If he has not been digesting properly (perhaps combined with overlarge food items) he could be impacted. Soak him several times daily in warm (not hot) water. Increase the temps immediately. A little Acidophiliz or Bene-bac(one or the other usually available at pet retail outlets--try the bird section if you can't find it in the reptile section)won't hurt.
You also need to have a fecal done to check for parasites. See the posts above under "help...emergency" for a little more info on parasite testing and treatment, and emergency feeding tips.
Finally, please be aware that live prey should not be left in cages. Crickets need to eat too and they will bite your dragon. If you can't get smaller crickets, try some alternate food items(not mealworms!). Silkworms can be ordered (as can smaller size crickets) and are excellent. Superworms are okay in a pinch for adults but can be a bit large for a baby and are too high in chitin for a delicate system. Wax worms are candy--tasty and worthless.
Good luck and hope everything gets better for your dragon.
Best,
michele
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4.3 Bearded Dragons (Rescues)
1.0 Corn snake (Rescue)
0.1 California King
4.5 Royal (Ball) Pythons (3 rescues)
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