Female beta fish fight?

I recently bought two FEMALE beta fish. When I first put them in the bowl, I didnt use th divider that came with the tank. I noticed the red one (which is bigger of the two) chasing the orange one around. When i woke up this morning, the red fish had eaten some of the fins off...... NOW, the orange fish just sits at the top of her side of the tank and barely eats. What's wrong!!? and what should i do!?