why do I feel like a bad person if I was a child?

I am 20. Around a month ago, I suddenly remembered something very bad I did when I was ten. At the time (when I was ten), I didn’t think twice about it, but ever since I remembered it, I can’t stop thinking and obsessing over it as I do not understand how I could have ever done something so bad. It really bothers me, and now I am contemplating wether or not I am a bad person. I have read many articles about this, scanned them, looked for people who have done similar things. According to them, I have past event ocd. I can understand that, but I consider what I did too bad for it to be that. Here’s what I remember of it: When I was 10, my sister was 7, and around that age we would often just walk around naked, wrestle, and etc just like kids. This is probably why I didn’t think twice about what I did. At that time, I would hump various things, not knowing what it meant. I can faintly recollect humping my sister. I do not understand why I did it, but it bothers me a lot and makes me wonder if I am a bad person. I realise it’s horrible, but I didn’t know what I was doing at the time.

I was a weird child and i did some weird sexual things when i was younger (the worst part was around 6 or 7 but i also had some weird behaviors up until i was 12) and i truly feel like a monster right now and it all makes me feel like a pedophile because, even though my sister is only a year younger, she was always with me, we got a baby brother when we were 12 and 11, that’s when my ocd started. I think i might have done something to him but I don’t remember clearly

I was inappropriately touched by a few people close to me. All fairly young as well. I can’t help but think some of it was my fault. I also repeated these actions to other kids my age and traumatized them too. I feel so so guilty and awful. It makes me hate myself so much.