She might be looking for a boyfriend! No, seriously has she ever been bred? It seems like your husbandry is fine. What is the humidity percentage? Are there any signs of illness would be the other possibility? Noisy breathing, increased secretions coming from the mouth and or nose, any injuries. Ruling those out, a pacing reptile is a hungry reptile until proven otherwise. Keep us posted. Good luck. Oh, I see your humidity percent. Thanks.