Week 11- 2 weeks to go

Overall i feel as though i am on track. i have my background done for level one and all my characters and everything that is needing within in the game done. Now all i need to do is my background for the second stage. What i am having difficulties with is making my background for the second stage. How do i put in my background with out my background changing in stage one? Every time i change something in level two it changes the positioning of my objects in my first stage.