Annoyance, worry, discontent, irritation, dilemma, bother, bustle, trial, hardship, effort, affliction, ailment, malfunction, disease, worry, harass, grieve...
The root word for "trouble" is the Latin word "turbare," which means "to disturb or confuse."
Agitation is a synonym for fuss or trouble.
The word "reply" means the same as respond.
"Disrupt" is a word that means to disturb or cause worry or difficulties.
The Latin word for trouble is tribulatione. The Latin word molestia means worry and tribulatio means distress. This words are similar in the meaning of trouble.
"Ado" covers both adequately.
Antiphon means the same as feedback, interpretation, justification, result, or sign. Some antonyms for the word antiphon include problem, question, quiet, request, silent, or trouble.
Concern is the word.
It's a phrase, not a word, and it means you're in trouble.
Twinge, affliction, tenderness, agony, discomfort, suffering, anguish, grief, heartache, problem, vexation, annoyance, bother, trouble...
Surprised almost means the same as startled.
"Similar" is a word that means nearly the same as "like."