I think I abused my brother when we were children

Hello.
I come to you because I'm feeling terrible about what I did to my little brother when I was around or nine or ten years old. He is four years younger than me. I don't know how I came to do this, I think I wanted to try being a couple or something.
I used to sleep in his bed, I don't remember if he wanted me there or not (because we used to play games also, normal ones which he enjoyed). We would role-play, usually stories of spies or adventures... but I remember sometimes asking him to be my boyfriend, and I would lie next to him and kiss him on the lips. I don't recall ever touching his penis. Just laying close to him and kissing. Once I also asked him to kiss my butt, and for me to do it to him, he really didn't want to and my mother saw us and reprimanded me. It never happened again.
I can't remember how many times I did this, how long it lasted. The weird thing is, I had entirely forgotten it until sometime ago when it all came back to me. What if I forgot other things too ? I'm not sure I can trust my memories it's very fuzzy. What if I did worse ?
My brother never mentioned it since (he's 15, I'm 19), but I can't help but wonder if he's had remnant of what I did to him, if he's going to be troubled by it in his personal life, if he still recalls it. We are in good relation, like regular siblings.
I'm disgusted by what I did. I started being very adamant about consent and got interested in mental health, and that's when I suddenly remembered my actions. I feel like I don't deserve my family, even less my brother who's amazing.
I don't understand why I was like that as a child, because now I'm absolutely disgusted and ill-at-ease with touch in general. My friends know not to touch me, I never hug, never kissed anyone, I panic if someone restrain me physically, even just for play.

I'm unsure what anyone can do for me but maybe advise me something... Thanks for reading.

I'm hesitant to ask such an invasive question... but if (and I may we wrong) you have been abused yourself, I really think it's very likely that your feelings of guilt are confused reactions to your own victimisation i.e. you feel 'wrong' or 'dirty' and are trying to find a reason inside yourself. I don't know if you were acting our abuse visited upon you or whether it was just childish experimentation... but please have compassion for your younger self knowing that you are only 10-year-old, a very young child. Also, your brother was not so very much younger than you. I can see why you'd feel uncomfortable about this memory, but I really don't think it's fair, right or appropriate for you to consider yourself an abuser or anything like that, honestly.

Hello,
thanks for your reply. I have no memory of ever being abused, so even though I have wondered (in relation to my aversion to touch), I don't believe I should be looking for lost memories. I'm too afraid of creating false ones, and I think that by now, I would have remembered since I did consider the possibility.
Thank you, it helps to be told I shouldn't be too harsh on myself. It's hard to forget about this now, or to just dismiss it, because I know I did the thing I now qualify as one of the worse things one can do to a child. I know it was mild but I keep thinking of how reluctant my brother was. I have only one instance that comes back to mind but I feel like it repeated and I can barely stand the thought.

You were a small child yourself and I think it was experimentation not abuse and that both the law and the medical community would agree with me.