I agree completely about the last fear stage. I am concerned she is nervous at the groomers. Is this also a vets office? Dogs can smell the fear from other dogs ( this musk is pasted in the form of a gas if you catch my drift..)
However- if the dog is being roughly handled at the groomers, that would explain that one too. If it were me, I would hang out one time at the groomers. Or pop in unannounced..
The fact she is trying to play with other dogs once in a while is a good sign. The other post said alot of what I would have, but it sounds like to me she is just young. Do not overly reassure her when she is scared as actually you are praising her for being scared.