As long as it's handed in on time and it's the best you can do, does it matter? If you were leaving the whole thing until the last minute, that'd be different. But if it's the final bits of it, then maybe you just need to accept that this is part of your academic process?
When I did coursework, I always used to write absolute crud for the first week. I tore my hair out over this until someone pointed out that I did it every time. It was just my academic mojo warming up. Once I chilled out and allowed the crud to happen, life got much easier.
The only problem with last minute hand ins, is that you're not leaving contingency for things like computer/internet/network problems, which might prevent you handing in by the deadline.