Answer to Question 1
Your perception of stress is instrumental in how your body responds. Whether the stress is real or imagined, your body responds the same: Your perception becomes your reality. It is possible for two people to have the same experiences in their lives but perceive them in ways that causes one to experience high stress and the other to experience low stress.
Answer to Question 2
Physiological measures associated with increased stress include, among others, increased heart rate and increased respiration rate. Stress can also affect one's breathing pattern, contributing to shallower chest breathing rather than deeper diaphragmatic breathing.