咦你大姨妈的房子掉了
[yí nĭ dà yí mā de fáng zi diào le]
'Hey, your aunt's house fell off', which means 'you've got your period'. In Chinese internet slang, 'big aunt' is a euphemism for menstruation, so this could be used to ask if someone is having their period. But be aware that directly addressing someone’s physical condition like this might seem impolite or inappropriate.