I am a healthy 25 year old woman. I have low blood pressure and normal cholesterol levels. However, I started getting a rather sharp pain in my chest tonight. The pain is located just below my right breast. I was wondering if this could be from a pulled or strained muscle. About 10 hours before I started having the chest pain, I moved a couple of rather heavy boxes in my attic. I thought this may have caused it, but I figured I would have felt the pain right away or at least a whole lot sooner had this been the cause. Any thoughts?