China transit questions. I'm traveling back to the US from Bali.

My 1st stop is in Xiamen for 12 hours, then flying to Qingdao with a 2 hour layover, before connecting to Los Angeles. What type of visa do I need or am i eligable for a 72 hour visa fre transit?
My flight from the US only has one layover in Xiamen. If I've understood the process correctly, all I need is a 24 or 72 hour visa free transit. Os that correct? Thank you in advance.