My brain doesn't funcution when I think the work is too difficult

I think that many of us have had that problem. Where we have been rather frustrated with the situation at hand, with how hard the work is so our brains seemed to have locked up and refused to work for any moment whatsoever. But it is rather unwise to rather force the issue. I have tried to force my brain to work, to try and get it to work, but it really does not work as well as I would rather like it to do. At least that's what has happened. Take a nice, deep breath and just try and move to something else. A couple of hours later and a fresh perspective, after moving away from the task at hand is always rather nice, to really free up that brain lock that you might have. Otherwise it will be frustrating and frustration is the number one thing that defeats productivity. I do feel that this does happen to me, but I try after a brief pause, a brief break, to tackle the work anew. In anything not just school.

I think there is nothing wrong with your brain but with the way you think. You should focus on what is important, the question, the answer, not on all the bumps or side effects or questions that might pop up as well. So observe, ask yourself what it is about and look for a solution. this will make your work way easier.

Relax and stay cool and keep focus. You need a cup of coffee to back your waste energy. Nothing is possible. Sure you can make it. Good Luck.