Hi thanks for posting .
You have had second degree burn on your stomach, which is now heeling. al this is a part of healing process
you have developed postinfamatory hyperpigmentation
If the area is not raw, and covered with skin you can stop using neosporin
Apply moisturiser and vit e cream for a few weeks.
add a steriod
with a depigmentation
cream after examination by your doctor after a few weeks.
Hope this helps you