How Do You Get Work Done?

I am currently a university student and have a major problem: being able to simply sit down and get work done. I can set aside a day to work, whether it is homework or contract work, and I will be lucky to have an hour done before dinner time. The only time I can actually get solid work done seems to be after midnight under a lot of pressure (ie. a deadline the next day). This has led to too many 5 a.m. nights and turning down too many invitations to go out only to stay in and accomplish nothing. I have stopped playing games, stopped watching TV, tried reading the Seven Habits book, and am currently seeing what classical music does for me. I don’t think I have ADHD, and I am not sure what else to try. If it is computer work, the web is always a click away, and I can always escape to my imagination. I know many of you will have had the same problem. Can anyone please give advice on how to overcome this problem, be it a little trick, medication, or anything else?
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