Break the routine. First go to the doctor for help. Medication and therapy.
Get out and exercise in the evening. Take a walk, life weights, jump rope, bike.
Get off the darn computer and TV.
I know you are 14, but you are old enough to clean up the kitchen, do some laundry, make yourself useful,
Get to bed at the same time each night,
Force yourself up in the mornings. Have your mom wake you if she is up before you. If that mean getting up earlier than you need to to be, so be it, Get a shower, eat, exercise, get moving, do that for a week and you will be falling asleep at decent time at night,
And get to class, every single day.