Hi Christie and welcome to the forum.
First, have you looked at your betta from underneath? Put her in a clear cup and hold it over your head. Her eggspot should be right between her ventral fins, or the long fins that hang down. Usually from this view it is pretty obvious unless she's very young and small.
Based on what you're saying and what I see in the pics, though, I tend to think she is a female, just a more passive-aggressive female who likes her personal space. Some betta girls will actively chase others around, others will hide, and other girls will mind their own business unless someone gets too close.