1) Anxiety 2) Apprehension 3) Apprehensiveness 4) Bad feeling 5) Compunction 6) Disquiet 7) Doubt 8) Foreboding 9) Hesitation 10) Painful expectation 11) Pang 12) Pang of conscience 13) Premonition of evil 14) Qualm 15) Regret 16) Scruple 17) Second thought 18) Trepidation 19) Unease 20) Uneasiness 1) Anxiety 2) Distrust 3) Doubt 4) Feer 5) Hesitation 6) Mistrust 7) Qualm 8) Unease 
• (n.) Evil premonition; doubt; distrust. • (p. pr. & vb. n.) of Misgive
Mis·giv'ing noun Evil premonition; doubt; distrust. 'Suspicious and misgivings .' South. 
[n] - doubt about someone`s honesty
mistrust noun doubt about someone`s honesty
uneasiness about the fitness of an action[Lexical terms] uneasiness about the fitness of an action