Yes, exactly. When she first put on the ring at the start of the episode, her eyes lit up first, and the green light went from her body into the ring, not the other way around. The characters erroneously assumed the power came from the ring because that's how it worked for Alan Scott, and because they were never looking at Jenny when her eyes lit up. Indeed, Courtney figured out that she could absorb the lantern's power because she was also generating it. If she'd just been a normal human, she couldn't have absorbed the energy and would probably have just been killed.