my dog died (Lucy) ... at 2 years and 2 months.. she got hit by a var and died instantly from head trauma. How long is it normal to grief ?

It's a painful to my family. it took a lot because it was so suddenly. we buried her in the backyard and it was extremely painful. she was everything and she died to young.. the next day ; me and my brother found out the house was too empty and painful without our missing family member... we adopt a dog from pet co. she is 4 years old and a husky mix. were we too fast?