Im just sharing my observations on the bathroom conversation. It had so many layers to it, some pleasant and some unpleasant. Please note that I'm in no way challenging Sid's affection for Sana. There is a genuine bond there. Sid's emotions in that were very interesting.
He, I think, has bee taken aback by Salman's revelation about Sana's love, that too in front of the housemates. The private person he is, he surely hasn't liked it. Also it damages his game. The plausible deniability that they are friends has been blown apart. This will play on his mind. I personally think this thought was on his mind all through that conversation. Should I take things at face value i.e. we are good friends or should I accept that she is in love with me i.e. act according to the information that has been revealed. Any interaction of his with Sana will now be judged by the housemates according to the new information. He doesn't like that dynamic.
The utmost concern and love was also evident in the hugs and smiles. But he was extremely self conscious. All his verbal responses to Sana were measured. Also him moving away from her was to stop the physical teasing that they are so comfortable with. This he has done because of the feedback he has received.
The selflessness of Sid and Arti yesterday was heartbreaking and brought tears to my eyes. Sid not making an issue of the footage they were shown was precious. His sentence "Haan lagi tu par chal jane de" had this sense of I will let it go but I hope you see my love in it. Arti also put back all her issues and was selfless. I am hoping it would clear all of Sana's misconceptions.
All in all that conversation, Sana and Sid were expressing love but they were not on the same frequency, that is why it came across as a little uncomfortable. One is becoming more confident in expression and the other is a little more uncertain.