My first suggestion would be seeing a doctor, and being totally honest about your alcohol and drug use. As others have said, they can only treat what they know about. No need to lie, as it would be a waste of time.
Is this an option?
Second, AA is a great recovery program for many (and it should be noted it is one program, there are others.) Are you aware of AA meetings where you are in Japan?
Get your body sorted, detox carefully with medical assistance, and we can assist you with beginning a recovery program that makes sense to you. It is very early here in the United States. Others will surely chime in when it is a more reasonable hour. :-) Those in the UK have a head start, so you might be hearing from them shortly.
Again, glad to have you with us.