Angst - an acute but unspecific feeling of anxiety; usually reserved for philosophical anxiety about the world or about personal freedom.
Malaise - physical discomfort (as mild sickness or depression).
Turmoil - a violent disturbance.
Weltschmerz - sadness on thinking about the evils of the world.
Ennui - the feeling of being bored by something tedious.
Despair - the feeling that everything is wrong and nothing will turn out well.
Melancholy - a feeling of thoughtful sadness.
Morose - showing a brooding ill humor.
Gloom - filled with melancholy and despondency
Despondence - feeling downcast, disheartened, and hopeless.
Depression - a mental state characterized by a pessimistic sense of inadequacy and a despondent lack of activity.
Megrims - a mental state characterized by a pessimistic sense of inadequacy and a despondent lack of activity.