How do I know if it's depression or just burnout?

Burnout lifts when the stressor stops. Depression follows you into the weekend. If a vacation, a finished project, or three good nights of sleep genuinely restores you, that's burnout. If nothing feels good anymore, including things that have nothing to do with work, and it's been more than two weeks, that pattern is depression, and NIMH's symptom list is worth two minutes of your time.

The catch: burnout left alone can slide into depression. A free PHQ-9 screen gives you an actual number instead of another week of wondering.