Hi InDiA,
I really think you need to talk to a doctor about this and also talk to your parents. Overdosing on medication can cause a lot of problems and repeted overdosing can cause signifigant problems. Also, combining medication with alcohol is very dangerous as well.
You should find some alternative ways to cope, there is a long list of suggestions
here. you can look at. The alternatives will not give you the same affect as the medication and alcol but they are safer and can be really fun.
I am not sure why you would like to trip out, but if there is a reason you are doing it (and you know that reason), the reason or reasons, should be discussed with a counselor or therapist that can help you work through the feelings and other possible reasons for doing this.
Hopefully this is helpful and you can
PM me if you ever would like someone to talk to or need help.