Of course it's not selfish — we all miss our brave men and women who are putting their lives on the line halfway around the world. And many of us want them home as soon as possible, just as you do.
You have to trust that the decision to enter the Armed Forces has made your son happy. And remember that he loves his family and country so much that he's willing to put himself in such dangerous environs.
The only solace any of us can have is to pray or have faith that he will make it through this terrible ordeal safely. We're thinking of you.