Nouns

(n)anxiousness, disquieta feeling of mild anxiety about possible developments
(n)disquiet, unease, uneasinessthe trait of seeming ill at ease

Verbs

(v)perturb, unhinge, disquiet, trouble, cark, distract, disorderdisturb in mind or make uneasy or cause to be worried or alarmed“She was rather perturbed by the news that her father was seriously ill”