Dear Renuka,
I hope you are not with the same firm since 2.5years,as you cannot bear that culture.But why is it so that this firm has such a culture,since you are sounding quite genuine so its must that you have a word with your superior authorities.Just clarify yourself about the positives and negatives of the culture and in case you are sure you don't want to continue and even discussion didn't helps you out then certainly treat yourself right by planning for a switch over..
Regards
MK