What's gonna happen to us?

This Monday I was at a Burlington coat factory when my friend just started stealing this flask. I was looking around going "OMG I hope they don't see I just wanna leave!!!" in my head. Well we got caught. We had to empty our pockets inside this little room. Then we sat down for a while then a cop came in and questioned my friend (couldn't hear what was said) and made him write a report about what happened. Then she questioned me and then she said "You have the right to remain silent..." bit to me then asked me if I wanted to write a report and I said no. Then we sat in a room for like 40 and then my dad arrived to get me. I didn't see my friend leave. They said they could press charges (sue) and I had to sign a paper saying if I ever come back to BCF I will be arrested on the spot for tresping. Do you think they were serious about suing? I'm 15. What do you think will happen to us. My friend stole it and all I did was look around praying no one saw. The Flask was $8. So whats gonna happen