Hello all. Recently my left side (including the ribs, shoulder, breast and armpit) have had a burning/aching sensation. I don't think it's a heart attack (I'm only 24 and have had an EKG within the past year or so). I am worried it could be a spleen issue or something scary. Anybody have any similar experience with strange sensations on the left side? Or any experience with what spleen problems feel like? Or costochronditis/fibromyalgia? Any help would be so appreciated! Thanks!