I feel for you. I had a day like that last week. I left early and I was supposed to do CPR after work, but after a RN made me feel like an uneducated piece of pond scum I left (she said this after my shift was over and report given). I hadn't cried in ten years and I didn't make it out the door before it started. I cried all day and I didn't want to go back either. Then I reminded myself that I am better than that, and to never let anyone make me feel inferior again.
The whole reason I was a piece of uneducated pond scum? Housekeeping was moving beds and had moved a bed under the bedside chart (little thing that pulls down where you can write). Anyway, this nurse just couldn't muster the strength to move the darn thing. She demanded that I do even though I was busy putting in I & O's and answering the phone. Her response "well, everyone else does it." Felt like telling her that if someone jumped off a bridge she should feel free to follow.
Sorry to hijack. Next time you work, go in there with your head held high, smile and say good morning/good night to everyone. Trust me, they'll forget about it and something new will arise.
As far as the NM, it sounds like not much can be done there, unless you get a large group of nurses to talk to her boss. If I was in your situation, I'd be looking for another job before the NM really truly hated you (undeserved of course). Good luck!