i think that ridz was the one who admisnistered dadu the propanol.
armaan knows it coz he saw her with it during nov.12 epi.
i think he is angry and playing basketball (acc. to the now famous nov. 12 promo)coz he cant decide whether he shld tell dr.keerti the truth or keep it from her coz he loves ridz.
even the promo says ki "usulon ki jeet main kya hogi pyaar ki haar".
just a thought.wht do u guys think???