Short story: Depths Stare Back

We had wandered into one of the caves surrounding the limestone bluffs looking for a child that had run off after one of the raids. It had ended badly, one of them escaped during the negotiations, it ended that a traveling troupe of musicians being killed after they accused us of kidnapping the child that had run away. Cori lead the way with a small torch and her knives out ready for use. 
We swept back and forth searching all the nooks and crannies as we went on. Each shadow that moved made us jump. Sweat dripping into our eyes, clouding what we could even see. Every drop of water, twitched our ears at the sound. We shambled our way deeper into the dark tunnels, I scored the walls with another knife to point our way back out. 
The caves kept playing tricks on us, thinking we saw movement in the darkness, only to find it was a strangely shaped rock, or a hole dissolved through the floor of the caverns. As children we always heard stories of this cave, always hearing voices howl in the night. Of monsters that would come out and snatch away naughty kids never to be heard from again. We couldn't help but remember those stories as we searched.
Now, don't get me wrong, we were competent enough to handle whatever came our way, but it still lingers in the back of the mind. The slight doubt, puts you on a special kind of edge. We had come to a steep drop down that seemed to lead to lead to a bottomless pit. 
"Why don't we stop for a moment? Just a quick rest. Wipe the sweat off our brows." Cori had spoken up, she had been looking paler the longer we were in here.
"Alright" I answered "Why not." We sat down at the ledge of the drop off. 
I was unsure of how long we actually sat there, but it felt much longer than a few minutes. Time seemed to crawl by in here, as we didn't have the sky to judge the passage of time. Looking over at Cori I saw her eyes fixed at the bottom of the pit. I tried to grab her attention, but nothing would do it. 
"Cori? Are you alright?" I asked her, putting a hand on her shoulder. She pointed down into the darkened bottom of the pit.
I followed her gesture, and couldn't make anything out at first. I concentrated and thought I saw the glint of something metal. Not exactly metallic, but definitely shiny. I reached behind me for one of the torches, and dropped it into the pit. As it fell, illuminating the stone walls and a small pool of water at the bottom. There was the child, inside a picture frame at the bottom. 
"No, not a picture frame." I thought to myself. "It looks like a mirror..." I said out loud. My gaze slowly wandered to the ceiling of the cave, and the child was there on the ceiling. Posed, as if stuck there by something. I flicked my eyes back down to the mirror again, and realized I saw myself in it now. A slow creep of horror sunk into my sink.
Cori bolted up, grabbed me by the arm, and dragged me back the way we came as she sprinted away. I got my feet back under me as I heard my own voice start laughing behind us. We didn't stop running until we reached the village.