I am a Mom and I can assure you your Mom doesn't hate you but she does have emotions and you and your brother hurt her feelings, frustrated her and were a complete embarrassment to your family as a whole.
If you want to figure this out I suggest thinking about a time when someone you trusted betrayed and hurt you deeply. How did that make you feel? What was your reaction? How has your relationship changed? Did they care enough about your relationship to apologize?
Regarding contacting family services, I suggest using your internet time to read about the foster care system and juvenile detention. When you go into the system you and your brother won't be hanging out at McDonalds and you won't be playing Xbox and listening to ITunes. People won't be just playing with ketchup. If you get hit with something it will probably be a fist or worse.
Think about what you did wrong and make amends with your mother and your brother. You will feel better and be a better big brother for it. If you are honest with yourself, you will admit that you deserve to be punished. Accept that you made a bad decision and apologize to those involved.