1) Angst 2) Anxiety 3) Disquiet 4) Hypochondria 5) Hypochondriasis 6) Nerves 7) Overanxiety 8) Scare 1) Anxiety 2) Butterflies 3) Mental state 4) Psychological state 
• (n.) The quality of being anxious; great solicitude; anxiety.
Anx'ious·ness noun The quality of being anxious; great solicitude; anxiety. 
[n] - a feeling of mild anxiety about possible developments
anxiousness 1. A feeling of mild anxiety about possible developments. 2. A relatively permanent state of anxiety occurring in a variety of mental disorders.
disquiet noun a feeling of mild anxiety about possible developments