Im really guilty and a shitty person?

So I'm 25 now and when I was 12 or 13 I was in the bath with my nephew. I had a suit on and my nephew was naked. I reached underwater the water was dirty and felt something weird and pulled it up towards the surface and it was his private. I immediately let go. It was unintentional. I feel awful about this.. I had no clue. Like what if my sister knows this? She wasn't in there from what I recall but I feel so bad. What if she knows and is like holding it against me? She let me baby sit him after that.. it was a big mistake I had no clue... when I realized what it was I immediately let go. I had no clue what it was. :( I was a kid also, but what if my sister knows.. what if she's telling people this... ugh. My poor nephew he was 1 or 2. I can't remember that well. What do I do?

Im really guilty and a shitty person?
Post Opinion