Hi flores2231, I'm sorry to hear that you are feeling about yourself in this way.
Firstly, please rest assured that the situation you're describing does not fit the definition of child-on -child sexual abuse; firstly, the situation you describe is a normal one among children this age, they get curious about something and try it, anatomical curiosity and exploration is very common. What your friend said is important too, that she does not have any feelings of violation from it, just that neither of you knew what you were doing, being curious like children can be. The definition of abuse is very different to this, it has intent, rather than curiosity behind it and involves one child making the other do the action, to achieve an end result, see how this is different from a child's natural curiosity?
How does the above explanation sit with you? Would you like to talk about how you ended up on this train of thought? I know you've been having some conversations about consent and coercion recently, as LuC said in her other post, the important thing to do is to educate ourselves on what good communication and consent looks like, particularly when it comes to sex. Here are some good articles about that:
If the above prompts any further questions or thoughts you'd like to talk about, we'd be very happy to discuss them with you here.