You can divide your vast goal into short term goal. Focus on only today's study. Set some goal for short term which is achievable and less frustrating. By ding this your attention and focus will be more on solutions than on problems.
Even After setting short term achievable gals things are not improving , you need to visit counselor.
Next Steps
Psychiatrist or psychologist help for further assessment
Health Tips
Keep short term goals rather than focusing on overall things .
Set up study timetable and time management