My completely unprofessional opinion is that you may or may not have Asperger's. In addition to that, it looks to me like you might be manic, and have a reading/writing disability. I don't mean that in a judgmental way; it's just what I perceive.
I say "manic" because the content of your writing suggests that your stream of thought is kind of hasty and a bit grandiose (perhaps?)
I say reading/writing disability because you said it is an effort to spell, punctuate, and capitalize properly. I don't mean that as an insult. Those are things that come pretty easily and naturally to adults without a reading/writing disability.
I'm no expert, of course, but I've read a lot about these kinds of things in dealing with my son's issues.
You say you are failing school. I say your school is failing you. You may not see it this way, but as an adult with my own kids, I find it inexcusable that they allow students to have iPods in class, and have allowed you to get through to your last compulsory year without basic writing skills. The school should have caught that long ago, and worked with you on it. It looks like you have slipped through some cracks in the system, and that's not fair on you.