I think she already senses a problem..
Coz Shaan generally never behaves rude with anyone...Even Dharam se he doesnt behave this way...even though Dharam annoys him soo much...!!
So she will certainly know that the reason for Shaan's state is sum problem with his parents..
Even yesterday she thought Sunil wud scold Shaan for showing up late...so she took blame on herself saying ."It was my idea to go out late".....She didnt want shaan to be scolded again !!