I really don't think you should tell her. Remember that their first priority is covering their arses - so if you allude to doing (or having done) anything dangerous (and taking a weapon out due to paranoia most certainly constitutes this) then she will panic. I've said similar things to psychiatrists before - and it never ends well. Instead, I suggest you tell her in a non-specific way that you've had paranoia, which led to you having dangerous thoughts, but you know not to act on them. That way she can be assured you are safe, and that you simultaneously have the required "insight". That is, unless you wanted to go inpatient? However, I don't think that their vested interest to help patients really extends beyond giving out medication, so she will probably suggest you take medication for this.