discomfort vs warning bell

discomfort

noun
  • Something that disturbs one’s comfort; an annoyance. 

  • Mental or bodily distress. 

verb
  • To cause annoyance or distress to. 

warning bell

noun
  • A problematic or alarming aspect. 

  • A bell rung to warn people of a danger. 

How often have the words discomfort and warning bell occurred in a corpus of books? (source: Google Ngram Viewer )