A major problem that has only been hinted at here is that many of the drugs you mentioned are illegal or being used illegally. This is a multi-level problem. Illegal substances are not controlled, the source of the drugs could be questionable for quality, uncontrolled for cost, unsavory locations for transacting business, possibility of being caught, harmed, killed, blackmailed, arrested, the list goes on and on.
I can only imagine what a habit like yours must cost you. How do you support that? Are you selling drugs as well? Are you pissing away an inheritance? Stealing? You can't work a job that pays well enough and still have time for school, can you? If you do, tell me what it is so that I can quit my engineering job and go into that business.
My job takes me into prisons on a pretty regular basis; you DO NOT WANT TO GO THERE. I think the statisic is something like 90% of the criminals in the jails are there on drug related crimes. I don't mean to judge you, we all have our problems. I just think you need to get yourself help.