Pain after breast reconstruction

Two years ago, I had breast cancer and had my right breast removed and reconstructive surgery. I received no chemo or radiation. One year ago a discovered another lump on the side of my breast under my arm. I have had it looked at and they said, it was nothing. They did an ulta-sound but could not find it. Since then I have had pain in that area, the area where the lump is is tender to touch, and most recently the pain has increase and wrapped around to my back under my shoulder blade. My breast appears to be swollen especially around were my nipple would be. Sometimes the pain takes my breath away and it is always there now in some degree. Please help with what it might be.

[sweetpea03]

it could possibly be an infection...