qualms

(n) - Qualms are feelings of slight worry or doubt because you are not sure that what you are doing is right.

• Synonyms: anxiety, hesitation, indecision, insecurity, misgiving, mistrust, nervousness, reluctance, suspicion, twinge, uncertainty, unease
• Antonyms: approval, comfort, contentedness
• Etymology: The true date of origin is unknown, but it was Old English, from cwelan meaning "to die." This word took on its current sense of "feeling of faintness" in the 1520s.
• Morphology: quandary - n
• Example: I would definitely have qualms about going into outer space!