The jargon for the undesired movement that you're seeing is "boomerang" motion. Search for the word 'boomerang' on this page, and you'll find an explanation, a solution, and a link to a video about it.
BTW, your use of the word 'stage' tells me that you're new to After Effects and coming to us from the world of Flash. Welcome.
This post has links to a sample chapter about After Effects for the Flash user that you'll probably find useful:
You might also want to go through these materials:
Todd, this was exactly what I was looking for, thank you so much! I really appreciate you taking the time to help me out.
And yes, your keen perception was correct, I'm coming from Flash. I will be sure to read through those tutorials.