I went to a girls apartment building without calling ahead. What is this girls issue.?

first of all, she was probably with another guy at the time, or he just left or something. They all react like that when this is the case. But technically she has a point- if you two aren't exclusive, you should never show up unannounced. How would you feel if you were doing some hotty you just met and she just shows up out of the blue? I'm just sayin'...