A 17-year-old girl is brought by parents to physician with complaint of decreased sleep, irritability and lack of appetite leading to weight loss of around 4-5 kg in last 2 months. Patient herself repos feeling fine and in fact mentions having lots of energy. Physical examination shows a thin body habitus with a normal BMI, erythema of the nasal mucosa, and mild facial acne. Which of the following is the most likely diagnosis?