Chest pains

For years now I have been training and for some odd reason, when I work my chest out I get these pains from the left side under my armpits, under my left breast to the center of my chest by my breast bone. The pains are burning sensations and feels like someone has my muscle all clinched up in their fist. Just very painful and the pains progress even when I dont work out my chest. I have tried not working out my chest but even when I dont work out, the pains are there. I cant sleep on my left side. I do have large breasts for my size. I am 5'4 and weigh 120 and my breast are a large 34 C. They are heavy and after I run or take my kick classes, the pains in my chest are just unbareable. The pains run all thru my left side from my shoulder, under my armpit, under my breast to the center of my chest. I was told by my doctor to back off the caffeine to see if it helps due to me having acid reflux. I did this for 30 days and it did not help. The pains have seem to increase. I am to the point to where I can barely do any chest exercises or run-By the way.. I never feel any discomfort on my right side.. just my left.  Any suggestions? €

[FireSign]

mel, im getting simalar (if not, same) thing as you, but not when i excersise my chest (i harldy do anyway) but when i run, but for me its happening on my right side, near my lung, feels like a crmap, liek someones squeesing my ...whatever's there... i thought it would go away after time after an oporation i had, but its not, and i just had bleep test oin running today, for GCSE P.E, and onoly got lvl 7, didnt miss beats, just gave up cause of this pain (got pain form lvl 4, but endured it, too much though and scary caus ei dunno what it is). NONE of this was happening when i was in primary school, i was VERY fast frunner and could run for AGES and not get this painy., in about 80 metres at my fastest, now, im getting theese pains, if i run, what ever speed, they come in about 20 seconds. i just want to get rid of em

[mmbb123]

I started running about 1 year ago and have progressed slowly up to 2-3 miles.  From time to time I get a very sharp stabbing pain under my left breast that almost feels as if it is occurring with my heart beat and only stops if I stop running- I have tried to push through it but absolutely can't.  It happens randomly; sometimes shortly after I start and sometimes after running for a while.  I have a history of chest pains due to anxiety but these do not feel the same, and the anxiety chest pains come even if I'm relaxed.