Hey,you have altered sleep cycle ,go to bed and get at right time ,don't sleep in day time ,avoid coffee ,tea in night ,don't watch TV ,computer while sleeping , do exercise daily in morning , don't worry too much...Exercise and stay active. Activity helps promote a good night's sleep. Get at least 20 to 30 minutes of vigorous exercise daily at least five to six hours before bedtime..Stick to a sleep schedule. Keep your bedtime and wake time consistent from day to day, including on weekends....Consult physician.

Thumbs up for sleep hygiene described by Harisha,also try relaxation before bedtime by breathing techniques and reading.

Hi there, Sleep issues are invariably related to some underlying problem, like anxiety or depression. Your feeling of tiredness and subsequent irritability and lethargy is suggestive of poor quality of sleep, and a disturbed sleep architecture. You are too young to battle with sleep issues. I recommend you to consult with a Psychiatrist to resolve these issues. Good Luck.