Well, dragon to help your case out a bit. If were on the computer continously, the light emitted from your screen actually messes with the Pineal Gland - which secretes melatonin. Melatonin is the chemical in your brain which controls your biological clock, in this case your sleep patterns. There are times where i know for a fact i could go to be really early, cause im really tired, but if i sit in front of the computer, that feeling now goes away.
Also, my sleeping patterns are also screwed up majorly, for other reasons. Stress, depression, being overly happy/excited, angry.. etc, all affect our sleeping patterns
Try reading a book rather then watching TV/Computer etc, or listening to some quiet music. It should keep you entertained enough until you can fall asleep : )