Strange Behavior After Visit To Vet 2 Weeks Ago

[Johnny]

Hi, I'm new to this forum and I need some help. I have 3 year old dog. I would tell you her breed if we knew it, so I guess shes a mutt. Shes always been a very energetic and social dog. A couple weeks ago, she had been having some diherrea problems, so we took her to the vet. She needed shots for routine stuff you know, and some medication for the diherrea. We finished the meds and everything seemed back to normal.
This past week, a few days after the medication ended, she has been acting funny. She seems very unsocial. She'll spend all day upstairs in one of my family members beds, crying until she falls asleep. Well not crying, it seems that it starts when she knows one of us is around, as if to let us know something is wrong. When shes not crying shes breathing very fast. She is also keeping her toys with her. I walked her the other day and she would'nt leave the house with out her stuffed hedgehog. Its beginning to worry myself and my family and we don't know what to do. If anyone has had this problem, could you please help us out. Thank you.