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When bitches be going crazy due to their menstrual cycle. Periodbrain may cause: irrational thoughts, spontaneous crying, extreme anger, random freak-outs, freak-outs over boys, the creation of unrealistic scenarios and just pure bitchiness.
My Periodbrain was so bad today I couldn't stop crying or punching things.

Dude your'e acting nuts! Do you have Periodbrain again?
by browneyedchick September 19, 2013
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2
When you're on your period and for some reason everything you say just doesn't make any sense.
I had such bad period brain today that I told my neighbor his face reminds me of mashed potatoes
by Feminist probZ August 01, 2013
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