sir is dropping a good option for iitjee, i scored a 164 in jee mains 2015 , so this question came into my mind is dropping a good option if you are not getting any nit also..

Dropping is not a good idea even, but it all depends on target and prepration.
You should be serious for JEE ADV now, after result, attend the counselling, if you are getting NIT, then go for it otherwise any very good private college, lastly if not getting anything, then choose DROP for IITs only..
Good Luck.........