I have sharp pain on my left side rib and cant take long breath?

Well localized,: pain upon inspiratory phase suggests costochondritis, localized chest trauma, with either traumatic costochrondritis or a rib fracture, and finally in your age group possible spontaneous pneumothorax. A better history and exam with or without imaging studies would be a good idea. These are the more common reasons regarding your query. Call your PCP for an appointment