Small pimple like bump on end of incision after breast augmentation (photo)

3 weeks post op breast augmentation There is a small pimple like spot on the end of my incision. My PS had taken out a stitch in that area after I went in for my first check up. It's a little tender and feels hard. What could this possibly be? I will be scheduling an appt soon but wanted to know if any professionals have seen this or could ease my worry.