It is very common for dogs to have a second "fear period" between the ages of 6-14 months http://www.diamondsintheruff.com/dev...talstages.html
Usually this is a short stage but you should be careful to manage your environment to avoid any negative experiences. I would suggest perhaps attending a positive methods training class. It could also be a bratty stage but I think she is probably a little young for that. Either way you need to work through it.
14+ had some important information to consider as well. Were you holding her when she had these reactions? If so, another thing to consider is that she might be resource guarding you. That is an important bit of information because you would handle that situation much differently.
Definately consider a possible health issue.
Implement NILF but be sure to pair any NILF training with lots of positive reinforcement for any good choices that your dog makes.
Dogs do not get angry, vindictive or other "bad" human emotions. They do get scared, overwhelmed. Shredding a pillow is usually boredom, not enough exercise or seperation anxiety. They do not think my darn human left me so I am gonna pay them back by shredding this pillow or pooping on the floor.