Injections for flat male nipple?

Your incisions will go through a maturation #process after gynecomastia surgery. For the first few months they will be red and possibly raised and/or firm. As the scar matures, after 6-12 months, it becomes soft, pale, flat, and much less noticeable. You may experience numbness, tingling, burning, “crawling”, or other peculiar sensations around the surgical area. This is a result of the #healing of tiny fibers which are trapped in the incision site. These symptoms will disappear. Some people are prone to keloids, which is an abnormal scar that becomes prominent. If you or a blood relative has a tendency to keloid formation, please inform the doctor. Also, as you heal, the area may feel “lumpy” and irregular. This, too, decreases with time, and massaging these areas will help soften the scar tissue. The #compression garment helps reduce the swelling, and the longer it is worn, the more quickly you will #heal. It can also assist in the retraction of the skin. If you have any concerns about #healing, its best to ask questions of your surgeon or their nursing staff. It's possible the indentations can be addressed with cosmetic filler(s) if eligible. 

It is definitely necessary for you to consult in-person with an experienced plastic surgeon.  However, flattening of the nipple area after gynecomastia surgery may be due to scarring or over resection, or both.  It is usually correctible with scar release, fat injections, or sometimes both.

Generally, this is easy to correct.  Be sure to seek out  a board certified plastic surgeon.  Fat can often be used to add volume below the nipple.  Sometimes, as the prior surgeon mentioned, scar tissue can be released.  More common questions about gynecomastia are answered in the attached video.