where was she in her heat cycle at the time of spay?
could she have been pregnant at the time?
this is probably a dog with a shaky temperament anyway just settling in and becoming more comfortable in her surroundings
that is, the honeymoon is over
at 3 yrs old her temperament is pretty well set but it would also take up to 2 mos to see her true personality
how did you acclimatize this dog to her new home and new surroundings?