What is the Hard Bump/knot under my incision site? (photo)

I had breast implants removed a wk ago through the inframammary fold. Originial incision was through my armpit so I'm not familiar with what to expect in this area. Today I noticed a hard bump under one incision. The other one does have a slight firmness to it too but not as much. Is this normal? What is it & is this very concerning? Could it be an infection? I notice some slight pinkish color around the breast but nothing alarming. The purple stuff around the incision is glue.