Two months ago, while at work (sit at a microscope for 8 hrs. a day for 10 yrs. now), I noticed some twinges in my L breast
. I just assumed hormonal, but then I started getting twinges in my L shoulder, which turned into a dull aching and sometimes burning sensation. The area that it started out in was the side of the shoulder in the back, like under the arm. Imagine lifting your arm up, and right beneath your armpit, you rub the vertical area underneath.