Sir/mam I sudden loss all my intelligence and creativeness .I am very good in maths in class 10th and used to enjoy it's solving problems and also very good in science. But in 11th class I loss my understanding and concentration skills I loss my thinking power by 50-60% and whenever our teacher takes lecture when all of my classmates says 'yes sir' to every point my heart always says that they are lining. And whenever I try to solve a maths my heart always says me "Leave It" I hardly concentrate 5 minutes. And do silly calculations mistakes in it. And in 10th I used to ask and ask questions to teachers but now I don't bother even if don't understand the concept. Another symptom related to it (may be).- I used to very thin in class 10th and eats a lot. But now I eat less and develop some fat in belly.