perfect plot!
well that's a good logic. However, I think this is what happened. Armaan and SS had a one night stand, and neither Armu nor SS got to know each others names. When SS saw Armu's photo in newspaper she came to Mumbai to get back in touch with him. And that's why she was carrying the newspaper with her. You probably noticed a bag on SS in the scene. Looks like she just arrived in Mumbai in search or Armu. Oh well we will find out soon....
dil kya kare
thats storyline is possible too ...but the HINT is what arman said " if someone loves me dearly should i love her back"
so SS must have been someone who loved him dearly and has come back now ,But if jassi comes to know then we all know what she will do ......
jassi jaisi koi nahin afterall