Hi, all these are due to real life problem. because you are not able to do study and now it's a usual reactive behaviour. If you think that you have only study problem and nothing else then should try concentrating activities like relaxation exercise, deep breathing etc. But along with forgetfulness and difficulty in concentrate if you also have other problems like irritability, anger outburst, difficulty in falling sleep, low mood, pessimistic thought, impaired appetite and self care than please visit a psychiatrist. You might be suffering from depression. Still you think you are not satisfied with all these please visit a psychiatrist. He would definitely help you.