cold feet vs cold sweat

cold feet

noun
  • A feeling of nervousness or anxiousness causing one to reconsider a decision about an upcoming event. 

  • Used other than figuratively or idiomatically: see cold, feet. 

cold sweat

noun
  • Perspiration which feels chilly to the person perspiring, and which indicates debilitating illness, shock, or the experiencing of an intense emotion such as despair, anxiety, or, especially, fear. 

How often have the words cold feet and cold sweat occurred in a corpus of books? (source: Google Ngram Viewer )