disquiet

(noun) a feeling of mild anxiety about possible developments. Synonyms: anxiousness.

(noun) the trait of seeming ill at ease. Synonyms: unease, uneasiness.

(verb) disturb in mind or make uneasy or cause to be worried or alarmed. Synonyms: perturb, unhinge, trouble, cark, distract, disorder. Example: "She was rather perturbed by the news that her father was seriously ill."