What should I do?

[blkgrphn]

My youngest (16 year old) brother had a huge party last night, because my mum and Mark are in Bali. We have bottles and cans everywhere, my mums car window is broken, the house has sand and mud everywhere and people have lost phones and camera's. The police apparently came. Elle was left in my room so she wouldn't get too scared. I was at work for most of the party, and when I came home I just ate my dinner, watched Angel and Buffy and wrote notes in my room. I didn't find out that he was having this party until yesterday afternoon when they started to set up, and there was nothing I could do to stop it. My brother is currently hungover and unable to get out of bed. Should I help him clean up? or should I just stay in my room, study and watch Buffy and Angel? I know which one I'd rather do, but if I don't help clean up I doubt it will get done. But if I do, I'm the only one who will do it, and I have exams to study for (and Angel and Buffy to watch).

Edit: They've managed to clean most of it. I'm upset because some of my loot (in the form of water bottles have gone missing).