Why do I eat and sleep all day?

Probably depression. Depressed people can have a more agitated type of depression where sleep is poor, anxiety is high & appetite poor, or the opposite may occur where they sleep all the time & eating is a compulsion that has nothing to do with appetite (or hunger for that matter). Obviously there are various combinations of the two. Is sleep and eating an escape or substitute for something missing? See your doctor.
Possible depression. What or describing are typical signs of depression. I would recommend a healthcare professional evaluation of your mental health as it may help. Also reading on mindfulness is a helpful way to deal with anxiety and depression without medication.