Replying to Applecare Question

Alright so this morning I tried to start my Black Macbook up and it turned on and I heard the chime and the monitor lit up for a second then went black. Now i've looked all over for a solution and even did the steps on the Apple website but no success. I'm pretty sure my harddrive failed which is going to be a huge lose since I have all my school work on there. I just made an appointment with Apple to check my computer out in a couple hours. I do not have the Applecare plan and my computer is out of warranty by a few months.

So my question is if I take it in today and they figure out what is wrong and they won't cover it will they blacklist me or something so I can't purchase applecare and then take it back in a couple days?

And does Applecare cover harddrive failure? I've checked the website and I can't see anything that states they will cover it.

Hope this makes senses and if you have any suggestions please tell me.