What does growing cold mean said in the following passage?
She checked the other bedrooms and bathrooms upstairs. She went up to the attic, checked the guest room. She went back downstairs and opened the basement door and called his name. No answer. She went outside, yelling his name now, running through the backyard, the pool area, the garage, the driveway, the front yard. Her heart thudded against her chest, her neck, her temples, her hands growing cold, but she told herself that she was being silly to worry, that he was a big boy, not a toddler. She imagined Alex laughing at her paranoia.
Does it actually mean that the body parts become cold as a natural humanic response to fear, or does it mean something else?