Depression vs mania

Increased energy
Activity and projects increased
Spend more money

Loss of energy
Activity and interest decreased

Decreased need for sleep - but not feel tired.

Disrupted sleep patterns: trouble getting off to sleep or waking in the middle of the night, or waking too early. Sometimes hypersomnia (oversleeping).

Feel good, high exhilarated.
Think yourself chosen, special, gifted, entitled
Libido increased.
Thinking speeds up, disorganised, a flood of ideas.

Feel down, low, empty, worthless.
Think yourself useless, a burden, the cause of all your problems.
Libido decreased.
Thinking, concentration, decision making impaired.

Speech can be pressured (not enough time to convey the flow of ideas), garrulous, inappropriate.
Perception and sensation heightened, in the more severe cases, the experience has an underlying level of agitation.

In melancholic depression speech can be slowed down, there is poverty of ideas, impaired concentration and a lack of interest and pleasure.
Perception and sensation dull. In some cases certain senses such as taste and smell can be abnormally heightened.

In severe cases there are grandiose delusions, e.g. the person believes they are God, or that they have a plan that can save the world.

In severe cases of depression there can be 'nihilistic' delusions, e.g. believing that their body is rotting.