I'm always catching my breath and experience tightness in my chest. what could be the reason?

Hyperventilation: Young people with chronic recurrent feeling of doom, rapid heart, breathlessness, & chest pain are often experiencing chronic anxiety & consequences of hyperventilation. Absent disease or abnormal blood tests, hyperventilation looms large as diagnosis. Relaxation therapies, meditation, yoga, mindfulness therapies, biofeedback, heartmath.Com, & the "relaxation response" by dr. Benson are useful.