She is just a little baby still, and would be leaving her breeders at this time if not for you taking her early. Just be positive, ignore the scared act(don't tell the pup "its ok", or coddle her) and go forward~ have treats or a valuable toy with you. Praise her when leaving and go for short periods of time, leave, come home, leave, come home repeat... Remember until she has had her series of puppy shots(10 weeks) she is vulnerable to parvo, etc..be careful.