2D Physics Problem?

Hey,

I recently started a 2D physics platformer following a tutorial. And when I add a 2D rigidbody & box collider to to the player sprite, when hitting play, it just hovers in a slightly higher position instead of falling to the ground. It's probably something simple and I can't figure it out. It worked once in the beginning with a different sprite but then it stopped working all together

Any help is appreciated and I can provide screen shots if necessary.