I believe it needs more light. It is plenty large enough to bloom, but the 'healthy dark green' foliage is a sure sign of insufficient light.
But please be careful, and don't just stick her outside in direct sunlight, you could burn her. Slowly increase the light in a brighter window and keep an eye on her. Bring her up to the light levels when her leaves start to look yellowish, and maybe pull back a tad. Good luck!