Savannah Monitor Shedding and Eating problem?

I have a Savannah Monitor that'll be 1yr old 04/26/10. I've had her for two months today and in that time she still hasn't shed once for me. I'm kinda gettin worried about that mainly cauz my friend has one and it seems like hers is constantly in shed. As for the eating problem well when I first got her she was eating well, most every other day or so. Then she just stopped. She became lethargic and didn't wanna eat. I took her to the vet and he gave me a medicine that was suppose to get rid of any worms, make her wanna eat and not be so tired. Do you have any idea what would be wrong?