I just started getting this pain today. It's very similar to what you all have described it's this sharp pain where there wire would be to my bra and it's only on the left side and they're like pulsating pains I'm not sure if it goes with the best of my heart (I don't believe so) I'm 28 and 5'3 120lbs so I don't think it's a weight issue (sorry I do not mean to offend anyone by saying that)... I also have anxiety and things have been stressful for me lately ... I wonder if that is playing a factor into it... I know for me when it starts my anxiety makes it worse I begin to get other physical issues ... Rapid heart beat,sweating, hot flashes... Hopefully it's something like muscle being sore... I don't need anything to add to my anxiety!!