IDIOMS

bundle of nerves

(idiomatic, dated) A lively, continually active person.

Example: 1895, Thomas Hardy, The Hand of Ethelberta, ch. 22:
  Being in point of fact a complete bundle of nerves and nothing else, his thin figure shook like a harp-string in painful excitement at a contretemps which would scarcely have quickened the pulse of an ordinary man.
1972, "Sudsy Whiff of Humanity," Time, 27 Mar.:
  She is a jittery bundle of nerves rather than the tough stoic she ought to be.
1883, "Talk Across the Table," New York Times, 5 Nov., p. 4 (retrieved 15 Apr. 2009):
  "Come and take lunch with me." The speaker was a walking, talking bundle of nerves, clothed in black broadcloth. A flawless diamond sparkled on the scarlet scarf that peeped above his close-fitting Prince Albert coat, and a pair of roguish eyes danced above two rosy cheeks.
1914, Edgar Rice Burroughs, The Mucker, ch. 8:
  He found Pesita pacing back and forth before his tent—an energetic bundle of nerves which no amount of hard riding and fighting could tire or discourage.