sathi i also had problems like that until last week... midterm ayo, dherai padhna parne bhayo so automatically change bhayo sab kura.. achel chai sutnai man lagdaina.. coffee helps you to keep awake.. basically you need to try hard for a few days.. tespachi bani parcha.. sarir bhaneko jasto banayo testai bancha tara tehi ho dherai pelyo bhane chai birami sirami parincha.