Hello Narayani 

To receive call from IIMS one need to have CAT score above 90 percentile. Though this year some of the CAT aspirants received calls from top IIMs because of their strong academic background as it holds some weightage. 

Since you have done quite well in your exam you can apply in some other top B schools as well. You can apply in Great Lakes , SP Jain, SIBM pune etc. So if you want to do MBA this year itself then apply in these colleges with keeping in mind some other colleges too and start preparing for GD/PI.

Good luck for your career ahead.