It did not happen in one day, it took long to be in such a stage where your son is now. It’s better to be calm with ur son, involve someone else to talk with ur son, give ur son love caring, don’t talk harsh, don't abuse him, give him chance to understand, try to find his friend who is better in practicing and request him to help ur son out from drugs and all, in last pray for him
I have a 17yr old son very rebellious. Recently I have caught drugs in his room and he has denied the usage. He doesn't want to accept that he is wrong. For studies he has all types of excuses. He neither offer namaaz nor wants me to tell him about religion. Only he follows moharram that too without attending any majalis. He doesn't want to listen anything. As a mother I'm too worried and desperate .
I am very sad to hear this. Inshallah he can make it out of this spiritual rut. I would suggest that you have him watch this show with you and perhaps it will open his eyes.
https://youtu.be/GHMSxpflqPM