Better safe than sorry! While your replacing the receptable replace the breaker TOO. I myself would try dead shorting the breaker just too see if it trips. Then replace it no matter what!
The reason I say short it is if that if the breaker doesnt the OTHER breakers in your panel may be bad too!!
!!!!If your panel is FPE!!!
Attention you have a known well documented fire hazard! The FPE stap lock breakers are TERRIBLE! just google FPE
REPLACE PANEL IMMEDIATELY!