What is this white-ish spot in my incision? I am 4 weeks post-op BA today. (Photos)

I noticed this white spot in my incision today. I have no fever, both my boobs dont feel hot to the touch but I feel tender in my incision, just like it always has been for the past few weeks during recovery. I had 450cc silicone implants. Everytime after my shower, I blowdry my incision with cold air frm the hairdryer so I am keepin it very dry. I also quit smoking to avoid complications. Pls advice as Im very worried. What could it be? Thank you.