Then again, perhaps the point isn't that "doing wrong" isn't sin but that even though it is sin we don't have to be dominated by it - but that we subdue it by not persisting in doing wrong.
Thoughts?
Genesis 4:6Then the Lord said to Cain, “Why are you angry, and why is your expression downcast? 7Is it not true that if you do what is right, you will be fine? But if you do not do what is right, sin is crouching at the door. It desires to dominate you, but you must subdue it.”