Chill for some time, next week try to thing or go back to your time when u were doing RC during GMAT test, think what u were doing, ur thought process, were u condfident while answering, if not, this i could have done etc etc.. , so just think and u will come to know where u have to focus, there is lot RC improvement tips on forum just search.
I am telling u, doesnt mean i am expert in verbal, i too trying to improve..

. All the best for next time!