Commit yourself to JEE as early as possible.
A JEE selection is as good as representing India at olympics. It is equivalent to becoming an MLA. At this point in time, your JEE selection is definitly equivalent to such achievements. It gives you the potential to achieve bigger things in future. Whether you will become an MLA or MP depends on how you use the opportunity in subsequent days.
I am writing this similarity so that you can feel the importance of your venture.
Early in life, secure your ranking in the society. Then you only have to maintain it from a position of advantage. Others have to challenge you from a position of disadvantage. They require three times effort to displace you from your rank.