I frequently need to take deep breath since last one month. I don't know whether it is called shortness of breath, breathlessness or something else. No problem while walking, jogging etc...I have BP machine at home, and everytime i measures, it comes normal. My vitamin B12 level is 206, thus i took injection for vitamin B12 as well. But still problem continues. Sometime it becomes normal, again sometime i feel that i am hungry of air or oxygen and need to take deep breaths. Please tell me what can i do to breath normally, smoothly as earlier.