My question involves criminal law for the state of: Illinois

When I was 11 years old, a friend and I light a field of grass on fire. I'd say less than an acre was burned. We ran away and the fire department came to put it out.

A week later my parents got a call ( I think from the fire dept). I went to the police station with my dad and I remember nothing involving the police other than just going to the station. I do not recall any legal proceedings or even talking to police personally. I took a fire starter program at the fire department and someone from the fire department explained something to me , however I forgot exactly. Something about them keeping a record of the event at the fire dept. and that if I did nothing else, it would go no further.

Anyway, at 17 I got supervision for a felony theft ( charged as an ordinance violation). My question is what exactly did they do about the fire setting? Could I have a conviction if I never went to court? What exactly is on my record?

Thanks