Dog people?

Ktrevey

I know this is a totally weird place to post this-but I figured I would see if anyone knew. I just made a friend who has a dog (who my dog plays with at the dog park) and she brought over her dog to our place today. We have never had another dog over before, well my dog got CRAZY aggressive with his toys and his crate... Like turned into a dog fight, I have never seen him do this before. So I took away the toys and then the dogs were fine and just slept on the floor and really didn't care about each other. We walked them together and they were fine. When ever we have gone to other peoples houses he is totally fine with toys and everything.

  Well, I am watching the dog Wed-Friday and I am worried that my dog will get aggressive again and freak out. Does anyone have any animal behavior tips?