Green’s Dictionary of Slang

period n.

(S.Afr. gay) anal bleeding following anal intercourse.

2003

K. Cage Gayle.

SE in slang uses

In phrases

have a period (v.) (also on one’s period)

to become emotional, agitated.

1981		G.V. Higgins Rat on Fire (1982) 39: If you’re gonna have your period here, go have it somewhere else, all right?
1991		W.T. Vollmann Whores for Gloria 98: I never said that to anyone Dinah, said Jimmy, so don’t go and have a period about it.
2018		G. Gilmore Class Act [ebook] Davie [...] having a period about why he wasn’t going any faster.
2019		N. Walker Cherry 43: ‘Okay. That doesn’t really help me but thanks.’ ‘Gosh, look who’s on his period’.