Isuckitis is real and it is dangerous to writers. When you are pounding out your first draft you can't stop and worry about the details. You can't stop writing until you get to the end.
There are dangers. That little editor in the back of your head is normally helpful, but today he is spitting out insults about what you just wrote. You heard the voice right? The one that says this is terrible stuff that will rot your brain.
Isuckitis is all your doubts and fears rolled up into a ball keeping you from the keyboard or urging you to press the delete key. It is worse than writers block because it doesn't just stop you from writing anything new, it makes you want to throw everything you just wrote into the trash.
I've been feeling this way a little lately. I had to try to get started writing again after a long stint of nothing. It's hard and I know what I am up against. My first draft is all about getting the words on the page and then I have something to work with. I need big numbers everyday to keep me going. Pages that can't be blank. Every one of those 300 pages has to be filled with words. So what do I do? I set my timer and start typing. I try to run as hard and fast as I can and jump over the wall when I run into it.
After you finally finish the first draft you can let your little internal editor out of it's cage and go to town. This is where you need his help to get the story just right. Until then you may want to put a gag in his mouth.