Check this out we know in indian serial never a relationship is easy anant and navy coming from a very stric family background and have to be more careful. But in love you can never predict when it's gonna happened or where.
Anant saying to ranbeer he doesn't believe in love and suddenly start acting like the way he is I think he's been touched by the shyness and the simplicity selfishness of navya who is not pushy but can show him that even being shy she had a strong caracter and stand against him ( during the tutoring of the computer project).
Anant probably find the opposite of Sonia in navya and he wants to protect her against all odds and something this feeling : new and unknow from him start growning (love).
And I think after navya's confess to him he was so shocked to hear all the emotions and feelings she confessed match with the way he was feeling for her that's why he came back and hugged her.
But do they really know this feeling is love? If they never experiment it before ?
I am sure when they will back home with Rama schemes and navya commitment to her family things won't be easy this is when all the twist and intrigues will start and actually we Will have things moving slowly.
What do you think guys?