I agree that it does sound like your gecko has MBD. I would definately take your gecko to a vet and make sure it's a vet that has experience treating not only herps but geckos as well, I made that mistake once and it only made my gecko much worse. The vet actually reccommended putting a UV light on him 24/7 and that I take out all of his hiding spot "shakes head", I can't believe I listened to him.
Check your vitamins, it's unlikely, but they may have expired. Also MAKE SURE that your calcium dust has D3 in it, that is the most important part when you are giving calcium. Besides using UV lights there is no other way besides D3 that the gecko can absorb the calcium. Is she still eating? If so she most likely still has a chance, if not it will be really difficult, but she could pull through. If she is not eating you can make a mixture for her to eat through a syringe (but be careful, feeding through a syringe can be extremly stressful for your gecko and she could even choke). I think Marica from Golden Gate Geckos has an excelent mixture, e-mail her on her link above. Otherwize just blend together the vitamins, some crickets, baby food if you want, and a little bit of water. When dealing with a sick animal the most important thing you need to remeber is to keep it hydrated with water. If she is not drinking you need to syringe feed her water.
Good luck, sorry if this is all old news to you.
Lisa
P.S. as the other poster said bearded dragons NEED UV (I don't know if it's UVB or just UV) lighting. Sunlight from a window is the worst thing you can do if it shines on their enclosure. The window filters out all UV and the heat from the sun can be damaging as well (I know there are other reasons but I can't remeber at the moment). MBD can take a very long time to present itself (months to a year ) and once it does it is often too late.
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0.1 Hypo Leopard Gecko
0.1 Albino Leopard Gecko
1.0 Blizzard Leopard Gecko
1.0 Albino Pacman Frog
1.0 Lovebird (Tony)
1.0 Elkhound Cross (Otto)
0.1 Malamute Cross (Paris)
6.0 Bettas