No, must have been the wind.

Scanning your head back and forth slowly over the forest behind you, you narrow your eyes at some of the more suspicious looking plantlife, before deciding that it must have just been your mind playing tricks on you.

You turn your attention back to the door, playing with the lock for a few more seconds. It's rusty and stuck from age, but you eventually manage to loosen it up with enough ****. With a satisfying click, it pops open.

Standing up and giving one last look around the forest surrounding you, you step inside.