I just gave my step 2 this july, I am still waiting for my scores.
As far as the breakdown goes, the majority of the questions come from internal medicine, emergency medicine and trauma related emergency room topics. That probably is around 70%. The rest of the questions are from OBGY, Peds, Psych, Beh Sci, and other misc topics. Orthopedics also features frequently. The proportion of the other topics you get depends on your luck, for eg, I got plenty of OBGY.
Are you in a US Med School or an IMG?