Tekniko's solution has nothing to do with the number of event sheets you're using. If all of your levels use the same event sheet, you need to find a way to determine what the "next layout" will be.
Most of the time that'll be a global variable, something like CurrentLevel will do. Then, once the win conditions have been met (in your case, the collision of two objects), then run two actions, one to increment the CurrentLevel by 1, and another to Go to layout "Level"&CurrentLevel.