Contratentative

adjective
Descriptive of the state of wanting to simultaneously do everything at once and nothing at all.

Fool's Guilt

noun
Guilt suffered in spite of the reasonableness or necessity of the causative action.

Example scenario: An urgent request has to be turned down due to a lack of available time.

Numbsnap

noun
The moment of immediate, intense regret following a seemingly innocuous action.

Example scenario: The unplanned revelation of a previously concealed truth in the crucible of social interaction.

Mullmort

noun
State of anxiety brought on by trying to imagine the experience of death.

Rankthrill

noun
Sensation caused by the rapid souring of pleasure, tending to be more intense the more unexpected the pleasure.

Example scenario: Brief, enjoyable bodily contact that is soon revealed as unintentional, eg. a brushing of the shoulder by a close companion.