I know I have read somewhere that puppies often go through fear stages where they become more fearful of things. At what age does this normally happen? Or does it completely depend on the dog? How long does it normally last? I have noticed Jesse has been more nervous over the last 2 weeks or so...she wouldn't go outside the other day because there were birds out there!! She normally loves to chase birds. And she was absolutely terrified this morning when a couple of little tiny dogs started barking at her. Thankfully everyone was on lead so we could just avoid them. Is this the best response though? Or should I have kept her there (but at a distance) to desensitize her?