>>1355I was like you though I narrowly avoided being expelled. What you have done it probably not enough to fry your brain, you are probably just out of practice. The effects of weed wear off mostly and alcohol takes a long time to destroy your brain.
Suggest you read the book "A Mind for Numbers" which is about how to learn stuff effectively.
Then enrol in a community college or a MOOT course on coursera.com and get back into some discipline. Then take it from there.
Hint: no matter how smart you are, there is no substitute for hard work.
You sound young enough to turn things around.