Im definately not an expert but I can tell you what I have read over the past 6 months. Maybe it will help.
i am almost certin that he has some sort of parasite his poop is runny and smells worse than my others but that wouldent cause him to shake would it?
Shaking can have various causes. The most common leg twitching cause is MBD. Then there are neurological stuff as well.
Has he had calcium before you got him? If not it could be MBD and Ive heard it can not be completely corrected BUT with correct care and sufficient calcium it can be stopped from getting worse, some dragons have even shown slight improvement.
For the possible parasites youll need to have a faecal done. Better safe than sorry I say.
he is my rescue i dont know how they took care of him before and im hoping its not to late.its heart breaking having him get this sick right when we were having real progress
If he was eating still a while back I think there is time still. Just get him checked by a good vet ASAP. I know how it feels when rescues gets sick. Mine was a rescue too and 1st it was every parasite/worm and bad thing tht we had to erradicate and now her liver is enlarged due to growing stress and she hasnt eaten in a week.
It is terrible when your babies are sick (No matter what their age ) You feel helpless and want to climb the walls till theyre better.
Youre in my thoughts and I hope its nothing serious.
Keep us posted please