You just described me. I'm thinking it's normal during high school, but I don't really know. I think it affects my procrastination. I NEVER procrastinate, yet this year, I haven't done a single sheet of homework yet. I just copy down the answers in class and say I'll do good on the test. Which then I do. But i know I SHOULD be doing the homework so then i can actually discuss in class. I'm still pulling straight A-'s but I usually pulled better than that. I usually get home around 4. I play halo for an hour or two if i'm not hanging out with people, then I eat dinner at 6:30, watch any shows i recorded from 7-8, and then come on my computer for the rest of the night.
lol On topic: I'm not even allowed to watch tv/play xbox during the weekdays.. so I pretty much get home at 5, go on computer till 6, eat dinner, do homework, then go to bed. Every weekday.
Sounds like a mixture of mild depression, sleep deprivation and being a teenager. I've had quite a couple of close people in my life suffer from depression and similar conditions and I'd highly recommend going to see someone, a psychiatrist/counsellor/whatever. All the suggestions that people have mentioned such as more sleep, better diet and change of mental attitude is something which a professional will recommend but aswell as that you need someone to help you along the way and I know this from personal experience, sometimes you just can't do it on your own.
OH yeah, just be smart when you drive wrecklessly, smoke weed, drink alchohol, and **** a prostitute. I get it now.