You can try feeding her a small amount of baby food. Mix some chicken baby food with squash baby food and a little water. Use a syringe to feed her. Try dropping a little on the tip of her nose. Most dragons will begin licking it off. If this doesn't work, you will need to force feed her. Only feed her a small amount at first - maybe one cc or so. Gradually feed more if she begins eating again. However, do NOT feed her until she has proper lights and temps.
Please answer a few questions about your set up to help us get a better idea of what her problems may be.
What kind of
UVB bulb do you have?
How hot is her basking spot?
What kind of thermometer do you use?
Do you use calcium? If so, how much and how often?
Can she still see the other dragon from her new tank?
Also, please consider getting her in to see a exotic vet. Try to find someone who specializes in reptiles and other exotics... Not just a dog/cat vet who will see a dragon. It is not the same - trust me.