I'd probably have to say that your game may have just glitched up. I'm not 100% sure, but that's probably my best guess. It could've just been the lighting in the room. You may have just seen trees. I don't precisely know... But You know now that I think about it, your game could've just not been able to load the cheat code so quickly. Remember, I'm JUST GUESSING, but that's what I think is going on.
Or... You're Just Lying... :|