Firstly, I wanna tell you “One single paper can not decide your future.” 

So Look forward and work hard until you will achieve your goal. There are so many exam behind the JEE like BITSAT, VITEEE, WBJEE & STATE LEVEL COMPETITIVE EXAM,So focus on this type of exam. Whatever you did the mistake in JEE, try to minimize in other exam.

Lastly, focus on your strength rather than weakness. Don't think much about the score and rank. Keep concentrate on study with proper way and nothing. Definitely you will get a good college.

Best Wishes for your upcoming exam!