Hi Nicolle,just read your post about experiencing  shooting pains in both breasts ,even though you onky had cancer in one breast. I had a lumpectomy ,and all my lympth nodes removed from my right armpit,as my cancer had spread there too. So that was in 2020. And yes i too do get pains in both my breasts,ecspecially when i stretch to reach or  pick sonething  up,and both my breasts are still very tender and sore to the touch. Like you i only had cancer in my right breast. But having my lymptj nodes removed caused me to go on to have mild lymphedma in my right arm  hand . I also got diognosed with rotater cuff inflamation on both shoulders ,so i just put up with the pain. I take paracetamols,and do rub a gell to help with pain. 

But yes i too think it could be caused by nerve endings and a build up of scar tissue aa well as my shoulder  rotater cuff inflamation,might be a factor as well.