In the past few months, I have noticed a fluttering sensation in my chest on the upper right side. It's not a painful feeling, more like a light fluttering, but it makes me uncomfortable because i'm not sure what it is. Sometimes it occurs while i'm working out and other times it comes on for no apparent reason, i.E. While i'm driving. Could it be related to stress, anxiety, birth control, or something else? If anyone has any ideas, please let me know. Thanks!