Hi I am a ca student and studying for ca exams. Suddenly I feel very low and sleepy and I sleep 10 to 12 hours a day. Another severe problem is my mind goes blank like completely blank I can't comprehend even a word said by the teacher I can't understand anything what he is saying. My mind is constantly thinking something and creating problems and trying to solve it. I have no control over my thoughts what could be the problem and what steps could be suggested.