Chicago - Beijing Capital Airport (AA) - Incheon (Korean Air)

Well, according to your situation, it's international to international transfer from T3 to T2. Generally speaking, the minimum transfer time is 2 hours. Thus, your time is tight. You don't need to reclaim your luggage at PEK. If possible, you can change the schedule of your next flight.
BTW, the correct procedures are the following:
Flight Arrival - Transfer Procedures - Stamped on the Boarding Pass - Security Check - Custom Inspection - Waiting & Boarding

Thank you so much. It helps a lot.
Unfortunately my flight is last one, I can't change it.....