My mom are about to sent me?

ok so I got caught smoking weed, this is the 2nd Time I got caught. Difference is this time my mom see me smoking. The last time I got caught, she say if she ever caught me smoking again she gonna sent me to live with my dad (he a drug addict, so my mom divorce him n now he live in Germany). Soo this time she say she gonna sent me away to my dad. I say I'm sorry but she don't really care anymore i feel so bad. I was stupid for even thinking to do it again. I did this cause is the last day of school. N I want to celebrate, I know I was wrong. My mom is a stressful lady she is very hardworking, she care for the whole family. She is also pregnate. What can I do now? What should I say to her? Should I move, I don't want to move. My future is to be an American citizens. What's the smart thing should I do now? Please help me on this one