I think I would be a little cautious, and while not trying to be overreactive have the vet do some blood work. Let him know that you want to know if there maybe any underlying problems that were not brought to your attention when you purchased her.   
In your case it doesn't sound like she came to you in a healthy condition. It could have all been caused by her previous living enviroment. Maybe she is a sensitive girl and her previous living enviroment was to stressful for her. 
You mentioned that she is 8 months old, cannot remember if you said she was bred by the breeder or if the breeder purchased her, again it could be stress by all the readjustments.  I would also want to make sure that she for sure does not have something she could pass on to my other pets. 
It could also be that she an allergy maybe to the food she had been on. Just remember when switching foods add the new food to the old food slowly, increasing it as you go. So as to not end up with diarrhea.  That would not be good.   
Good luck and maybe she is just a little unsure of her new surroundings and wondering if she gets to stay.     
				__________________  Proud Mommy to Annie  Muriel     |