Suspected Diversion

Hello.  My workplace recently has had me on a paid leave to investigate suspected diversion and appearing impaired.  It's been almost two blocks/sets of shifts I've been off.  We've had one meeting which was just awful.  I left shaking.  The union has been less than helpful. We are waiting to meet again.  What should I be doing in the meantime? Do I look for a new job? I feel like I'm going to be fired.  Please help feeling sick.  Was blatantly asked if I diverted medication and responded no.  Was told I've given large quantities of narcotics and insinuated I was impaired.