Is This a Blood Blister? (photo)

It appears to be a suture spit or stitch abscess. Keep it clean and dry and consider antibiotic ointment until it closes up. Let your surgeon know as well.

This is a deep suture that has not dissolved and worked its way to the surface.   They can cause pain and localized infection, so I would call your plastic surgeon to evaluate and remove the problematic suture.

I wish you a safe recovery.
Dr. Gill

This is a retention suture cyst that has drained. Use local wound care and notify your PS or see him/her//

This area is most likely a suture knot infection.  The suture knot needs to be removed and this will allow the area to heal.  

This is probably the site of "stitch abscess."  

A would guess that the suture is no longer present or it would be quite apparent. A call to your surgeon for advice would offer the best reassurance. 

Thanks for your question, all the best.