Hello thanks for asking from HCM I can understand your problem. You have symptoms like depressed mood, inferiority complex, fear, lack of concentration, low self confidence and thinking that what others will think about you etc. You have also complaints of decreased sleep. After reading your history I can tell you that most likely social anxiety resulted in development of depressive symptoms. Low self confidence, feelings that what others will think about you, fear, poor performance, inferiority complex etc are due to social anxiety. I would advise you to consult a psychiatrist for treatment. Medicines like SSRIs are used in social anxiety and depression. Fluoxetine, paroxetine, sertraline etc are used commonly. For events that provokes anxiety like in speaking with anyone, presentation etc medicines like propranolol, low dose benzodiazepines can be used. Consult a psychiatrist for prescription of these drugs. Try relaxation exercises, yoga to keep yourself relaxed. Thanks, hope this helps you.