Why, oh why...

I don't know what my problem is. I can manage to surf the web, read blogs, start several posts for my own blog, check email obsessively, respond to posts, check Freecycle and Craigslist, but I have yet to start my final for this class and it is due this Sunday!! I stress and stress about my grades, I have a 3.79 GPA that I don't want to drop, and yet I procrastinate and waste valuable time that should be spent doing any number of things rather than being on the computer most of the day. What is my problem?? I can not seem to get motivated, but I will be freaking out writing this huge paper at the last minute. I don't know why I do that to myself. I do not feel that this makes me work any better and it seriously makes me flip out and here I am again blogging and not writing my paper. Why?