You're on your period, but there's always something bothering you, namely Mark

You are holding back cramps in your stomach by squeezing the pillow tightly

but suddenly Mark came and said

"What's wrong with you? Menstruation? Weak." Said Mark sarcastically

You who are angry because of the pain in your cramps take it out on Mark by hitting his chest

"agh! It hurts..." said Mark, slightly in pain