I need some legal advice please?

Ok so a few eeks ago my buddy and I were going to a concert. he came over to my room as I was getting ready. He then told me that he wanted to go to Walmart to get some alcohol with this girl. I told him I would go becouse I needed to get some cash from the ATM. I had met this girl who lived on campus at some BBQ a few weeks back. When we got to walmart I went straight to the ATM and they went to the alcohol isle. When I got my money I went to meet them. When we were getting in line the girl went to a different isle not far from us with some food. My friend then payed for the alcohol and the lady asked for both our id's so we showed them to her and I helped my friend put the alcohol in the basket which he paid for I did not get any for myself. When we were leaving I asked why the girl went to a different isle and he said cause she was 19. So i dint think much of it since I did not buy it. When we got back from the concert we found out that the girl had been busted by the copsI need some legal advice please?
It's conceivable, but unlikely, that someone from the police department or the DA could ask you some questions sometime down the line... But if you didn't do anything wrong, then don't sweat it.I need some legal advice please?
I did it once and i only ot fined around 300 dollars or spent 10 days in jail i paid the 300, but you youreself should not be in trouble