Why sudden tightness/slight pain in pectorals muscle 7 weeks post BA. Even when I turn my neck, I can feel it pull. (photo)

When out and about with my kids today I suddenly started to feel slight pain and tightness in my right breast. I just had a hematoma in my other breast removed almost 4 weeks ago. The sudden pain makes me concerned. I can feel the implant more than usual underneath my right breast- when I push on it I feel that same pain in the upper part of the pectoralis muscle on that breast. Should I be concerned or did I somehow just overuse the muscle? I've been sneezing a lot but otherwise nothing crazy!