Hello friend you can re-attempt CAT if you are not able to score good marks. I like to share a story here. My friend has given CAT 2017 with just 20 days preparation and just got 65 percentile. Again he gave CAT 2017 with self preparation and attempted 10 mocks and he got 93 percentile this year. Though he managed to get around 97 percentile in Quant and DI section but in verbal he just got 72 percentile for which my over all percentile dropped to 93.This happened just because he has attempted very less no of mocks . So for CAT-2019 he is preparing again and planning to give as many mocks as he can to increase his percentile to 99.99 .

So I will suggest you to prepare for CAT with lots of patience and hardwork. And most important attempt as many mocks as you can.You will definitely get a very good percentile.