the mind > emotion > fear > nervousness or uneasiness > [noun] > nervousness > (the) jitters (4)
plural (usually the jitters). Extreme nervousness, nervous incapacity; a state of emotional and (often) physical tension; agitation.
A jittery or nervous person; an alarmist; an attack of the jitters. Also as adj.
Nervous anxiety, the heebie-jeebies, esp. in to give (a person) the screaming habdabs.