Just a vent about work

So I may be being super hormonal...but I cried most of the day at work today after being fussed at for a stupid reason. My boss currently has two offices. I work at his newest one ALONE. So we have a 23 year old pregnant girl working alone in a small town that's not the best with people constantly walking the streets. Long story short, I lock the door for my own safety because clients hardly ever come by and when they do they just knock and I go open the door. We maybe have a client come once a week...if that. My boss found out today that I lock the door and was furious. He didn't even call me himself to fuss. He got the office manager to do it. I'm just so mad that my safety isn't considered. Am I overreacting for being upset? I should also note that a woman in a town about twenty minutes away that was in my same situation got raped and taken hostage last year by a guy off the streets.