To the best of my knowledge bitsat score is accepted by bits only so getting admission in any other college on basis of bisat is not possible coming to bits itself so first of all i would like to specify that bits does not have any reservation so your category does not matter for getting admission here and since you have got only 90 marks so it is very difficult to get admission in bits even in bpharma as any score about 250 gets  you in contention to get otherwise it is difficult to get admission in bits.