Touching one's sister with lust

Two years ago I was sixteen and my sister was fourteen and we lived abroad and due to expensive accommodation we lived in a one bedroom apartment. So me and my sister slept on two mattresses but shared one blanket and one night I touched her breast but she was wearing clothes. But the same happened when we shared one bed and I was twelve and she was ten. But now I am extremely guilty of what I did and recently I prayed for forgiveness and felt satisfied and repent seriously and ever since that point I never looked at my sister from a negative angle. So now I want to know I can't definitely tell it to anyone so it okay to repent seriously to Allah and plus when I was twelve was I innocent because I don't remember that I had wet dreams then. So now what to do?