Check if record was edited or cancel button executed

I have a purchase order workflow that adds a button, then when that button is pressed a custom action creates a copy of the current purchase order and submits it. Then another action opens that po copy in edit mode. Then after the record is submitted another workflow is initiated and that po copy goes through an approval process. The problem is that if you press cancel instead of save on that po copy when it opens in edit mode, it gets stuck in the state that has the approval process workflow initiation. I need to somehow identify when the