These are a little more age approperiate, the bottom one is probably best.
http://psychcentral.com/quizzes/autism.htm
http://www.childbrain.com/pddassess.html
Regardless of the results, or what people think, it's all about getting him the help he needs.
Getting a dx isn't the end of the world, and while you might hate the label of it, sadly, that label is what gets the help and results.
Either way, it doesn't hurt to get him seen and to see if there are issues. Then you can start on the road to getting help. A year ago, my son didn't speak yet - now he talks all the time and is starting actually answer questions! He no longer hits his brother when he's trying to play, he actually plays with him. We wouldn't have that without the help.