Hi kashif, as you know your rank is not good enough, you must give it a try and for sure if you work hard you will surely get a good rank next year. All the best. Keep trying. 

Dear your rank is very low.I think this is your first attempt with 12th board.The board exams are quite different from JEE and you should not loose hope if you are hard working,disciplined,focused and also interested in studies.The first thing is that if you really want to crack JEE then please join a better coaching at any good institute in Kota OR in your city.You can crack JEE but ready for the stress management,time management etc.Please be sure if your 12 th percentage are good then you can crack JEE.But if you can't handle the stress then please join a good private engneering college and work hard there as wasting one year for preparation only is not advised.

Rest depends upon you.All the best for future.