What's that in the shadows?

You inspect the water, but see nothing there. Maybe a closer look will do. You approach the silvery surface of the water and lean in close. You think you can make something out at the bottom and lean in closer, and closer, and- oops! Your paw slips, sending you clamoring into the lake where your struggles against the currents are for naught. The last thing you remember is going around and around and around and then... down.

As you fall, you scratch your left front outer leg.

Under the whirlpool, a waterfall floats you into an underground lake. As you pull yourself from the frigid pool, an icy palace opens before your eyes. Thick layers of ice coat the cave's interior and ornate carvings decorate the walls. Your guide stands on the shore, shaking out her fur.  She inspects the surroundings, and you do the same. You realize there is no discernible exit, though some of the ice looks thin and even cracked in some spots along the walls.

What do you do?