I have a fluttering almost muscle twitch right under my right breast. it comes and goes and doesnt hurt. is it something i should be worried about??

Maybe: Muscle weakness and twitching are associated with many problems, some benign like fatigue, anxiety, dehydration, electrolyte imbalances, thyroid problems, nerve injuries, and some severe like stroke, encephalitis, meningitis, Lou Gehrigs disease (ALS), multiple sclerosis (MS). See your Dr for a full workup so that any serious problems can be identified and treated.