Runaway Hotline 1-800-621-4000
Hotline for Missing & Exploited Children 1-800-843-5678
Youth Crisis Hotline 1-800-448-4663 Try those numbers if you live in the US. They might be able to suggest some ideas for you. I know it must be very scary, but this isn't your fault. Just stay calm and work out what the safest and most sensible course of action is.
Normally, I'd suggest going to a friend's place or something, but you said that wasn't going to be possible. Have a think about some of your options. Your mum's behavior is not ok and she should not have done that.
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Also available in sober.