Is having a general disinterest in all things part of depression, or do i just not care about anything anymore?

Anhedonia: Loss of interest and pleasure is one of the depression symptoms, also referred to as vegetative signs. To be diagnosed with depression, however, other symptoms are needed, such as sleep and appetite disturbance, depressed mood, loss of sexual desire, feelings of worthlessness, etc. Best to consult your physician about your symptoms and seek treatment if needed.