Cathe,
I'm so sorry for your loss, but glad that you were able to spend 13 wonderful years with Hampton. Just know that his spirit will remain with your family through your memories of his playful antics and affection, and that he is smiling down on your family as a happy, healthy puppy forevermore.
I just got 2 kittens (Lulu and Kiki aka Loco and KooKoo), littermates that were abandoned at a (kill) shelter. They are the light of my life now - in spite of their mischievous behavior! It pains me to think of losing them, and pains me more to imagine losing one because they are so close - yesterday one of them accidentally shut herself in a bedroom and they were both miserable!
But I guess knowing that their lives are so much shorter than ours is the tradeoff for enjoying the years we have with them, and knowing that they love us as much as we love them.
Remember that time heals all wounds, and until then - vigorous exercise will keep those endorphins kicking and hopefully relieve you from your grief.
Take care,
Joni