How can you tell if the whispers you think you're hearing are auditory hallucinations or just the muted chatter of coworkers and paranoia that you keep hearing them mention your name but they really aren't?

I'm a bit concerned. Moderate paranoia is common for me, but this seems excessive, even for me. To add to that, I've had a noticeable (to me, which may or may not be paranoia also) problem with stuttering lately, very abnormal.