Weird Shape Tween?

1

I am creating a shape tween for a project and when I tested what I had done so far, I find out that the shape tween as some sort of rotation to it and I cant figure out why. On the frame right after the first keyframe that I use to start the shape tween, one of the squares angles is down some so it gives it a sort of rotation when tested. I cant figure out why it does this either. Any help would be appreciated. Thanks.