Coming into the U.S with expired U.S passport?

Question

I have U.S citizenship, an expired U.S passport and expired Panamanian passport. I plan to take an emergency trip to Panama flying out with my Panama passport, otherwise the U.S will not let me out if I try to fly with the U.S expired passport to Panama. I plan to renew the U.S passport in Panama. If I can't renew that U.S passport, can I still leave Panama with that expired passport and be safely let into the U.S. After all, I am a citizen. Thanks.