Loading multiple levels error

Hello i made a main menu and i wrote a script to load multiple scenes when clicking on a text by the mainmenu. theres three texts in the main menu Start, Credits, Instructions. and it does this error when i load my instructions scene it will go to the credits scene that i created. it seems it loads the last scene by the build settings. heres my script.

http://forum.unity3d.com/threads/85530-loading-multiple-levels-error?p=550700#post550700