Was I abused by my brothers friend?

When I was about 6 years old I vaguely remember my brothers friend (who was about 11 at the time) being at my house to play for the afternoon.

All I remember of the day is him pulling his trousers down and telling me to touch his penis (which I did) and then he would touch my vagina and it would go back and fourth like that until my brother walked in (aged 10), he was kinda disgusting and walked out and once his friend left I haven’t seen him since, I can’t even remember his name.

Do you think maybe he told my mum and banned him from coming back to the house? I remember it was one of the first times he had ever come over.