22 year old received 3500 FUE grafts in the frontal one inch of his hairline (photo)

In the US, this type of surgery would be considered malpractice. You have almost certainly used more than half of your donor hair for the recipient area that was transplanted, so if you lose more hair behind this, you may not have enough hair left to follow the hair loss behind the transplanted area. You must recognize that hair loss is generally a progressive process and you need to have a Master Plan to account for the progressive nature of your hairloss.  I hope that you don’t bald further but if you do, find an honorable doctor who understands such situations and will work with you with a high standard of care and management. Most young men are limited to between 5000-7000 FUE grafts during their lifetime unless their donor density is very high.