Hey Anshu.

See first of all be calm and have faith on what u have scored. 91 percentile is a good score in JE MAINS. But still if u are asking what to do then u can prepare for ur April session of JEE MAINS for more better performance. 

U can take admission in most of the private institutions by giving their exams which are of very low standard. See u are from JHARKHAND so u can also opt for BIT SINDRI this time as it will consider MAINS marks from this year onwards.

See no college is bad if u study well but don't panic at the time of ur judgement. Be patient think positive and try as many areas as u can. Give entrance exams of as many as college u know which are having a good record.

Hope u got ur point. Ask if any query.

Good luck