Please go back to your injector for an exam to evaluate if this is just a superficial reaction in your skin or deeper. It is hard to determine by pictures what the cause is .
Dr.Banta
Thank you for posting your photos. Your neck can be improved by removing some of the fat under the chin area. This can be done easily with KYBELLA injections. Kybella can cause some mild to moderate swelling and requires at least 2-3 treatments to see a dramatic difference and you need to wait...
Going into a steam room after Kybella injections won’t affect your results, but it could make you uncomfortable and increase the swelling. I’d stay away from extra heat until your swelling goes down. Consulting a board-certified dermatologist will help you make your post-procedure care choices.