Hi. My stomach is fluttering,the butterfly kind of feeling or the feeling you get when you are really nervous or scared in the pit of your stomach. I have been feeling it since yesterday night. I woke up with the same feeling and felt a bit nauseous. I am not scared nor anyting bad happened, but its out of nowhere and constantly reccuring at certain intervals. I am anxious for no reason. It is kind of hard to breathe sometimes and my heart beat is slightly faster than normal.Could something be wrong? could it be cancer? I don't have anxiety disorder. Is it possible something is wrong with my adrenal gland or any tumor? i googled and it said it could be pheochromocytoma.Is it possible? I am 17years old. Thanks.