Hello my friend. First of all don't be disheartened with your score, it happens with many people that they are not always able to cope up with their expectations in exams.

If you are really interested in engineering as your career and given that this was your first attempt, if you believe that you will be able to work hard, I'd suggest you to take drop for a year, study repeater's course at a reputed institute and try in JEE 2019.