Can someone please tell?

I just recently started watching this serial & I have been blown away by the maturity of the way everything is being portrayed so far. Love love it!

Just had this question about what happened in Sona’s past. She keeps telling she doesn’t want to get her heart broken. Also does Rohit know about whatever it is. 

It hasn’t been clearly shown wht happened. The only thing that has been shown is her engagement was called off that day as his ex karan ditched her and also attacked her probably coz she has a mark behind her ear which reminds her of that . Rest everything is Golmaal . Yes, Rohit only knows that much . The details of that night might b known after Raima makes entryin to their life .

Also on the day of her breakup with Karan she got involved in some kind of accident. Looks like Sona wanted to act on that but her mother held her back. This was shown in the episode during Pooja's wardrobe malfunction track where Sona forces Pari to accompany her to Sippy mansion.