So Close and Feeling so Far

So I have two papers to complete and I'm done... well, one now really. I have a paper due on Tue. this week, which is pretty much done, and another on Wednesday which I am trying to write now. But writing these papers has felt like I'm pulling out my own teeth, to add to the euphemism. I feel like I'm forcing myself to write and fighting the urge to just fill space with words that appear to make sense but really accomplish nothing for showing actual thought and effort. What compels me is the desire to finish well... that and each of these papers alone is responsible for the grade I receive in each of these classes. Is this 'senioritis?' Why does this happen? Thoughts, please?