What Causes Sudden Shortness Of Breath?

For a few months, I have experienced the need to have a bowel movement when I exert myself. It can be as simple as carrying groceries into the house, a load of laundry, even just walking across the yard. When this happens, there isn t necessarily pain.....just normal pressure. When this urge hits me, alot of the time it makes me feel nauseous & short of breath too even though what I am doing shouldn t cause a shortness of breath.