You have had the worst day.

You got your period, and you had been in so much pain with cramps. You went to work, dealing with the rudest customers, and on the way back your car ran out of gas.

You get home, the place a mess, and you need to make dinner. Whilst cleaning the kitchen, you hear the front door shut. Moments later two large hands are on your waist. You take them off, annoyed.

You're cleaning up, making food and dealing with cramps after having the shittest day. Of course you're annoyed. He didn't know you had your period, either.