I had ams a year ago while visiting frisco, co, which is 9700ft. i was then in er with oxygen. lately, i then very few times felt heart beat too fast. last week i went to guadalajara which is 5600ft and now feel sick with short of breath. need help. ?

Dr. can check again: Shortness of breath is not normal, unless it is the mild temporary shortness of breath with sports activities (but even then, one must be sure she is not having more shortness of breath than her sports peers have). Possible reasons for shortness of breath include heart attack, heart arrhythmia, heart failure, fluid around the heart, fluid in the lungs, asthma, a bad case of costochondritis, etc...