GUYS HELP ME OUT....ITS ABOUT MY FUTURE AND AM REALLLY CONFUSED!!!! HELP PLEASE....?

I didnt do well in my intermediate....nor in mt CET exam ( COMMON ENTRANCE EXAM FOR ENGINEERING) i will get a rank...in CET for sure but i know that i wont get into a good college!! if i want a good college in my state..i need to pay a lot of money!! and my preparations for BITSAT , VITJEE and other top colleges is also not good....and am sure i wont be qualified there!!! i want to repeat my 1 year of my 12th and prepare seriously for these top colleges ( VIIT , BITSAT, SRM , NIIT....etc) and am sure if i spare 1 year for preparation ill definately crack it!!! so is it worthy spoiling my 1 year...for these colleges?? or shall i join a private college in my state buying the seat....???? i wanted a degree from a reputed college like bits n all....so what should i do?? repeat one year or move forward now...in my view wasting anyear and getting into those colleges is quiet worthy because once ur there ur future is secured!!! and am ready to repeat my 12th...so it a good thing to do so or just move forward now!! wat do i do...???? HELP ME am just so confused.....