This might be a late response but I've had this happen to me several times and what i do is just write wrtie everything that is in your mind at this time it doesnt have to relate to your essay just get what every is is in your head out . That is the only wya I can set my head clear and listen to my thought then i write my essay as it comes is can look as crappy as posibble butthat is why it is called a draft. to fix all of those mistakes. try it out and see how you like it>