the advice about getting yourself a HPS lamp is good advice.
your plant will respond better to a lamp with the proper light spectrum.
Floros are good for growth, and can be a beneficial supplement light in flowering, but unless you have full spectrum or at least red spectrum floros, it is very difficult to allow the plant to reach its full potential. If it's just one plant, a 250 watt HPS(high pressure sodium) lamp will do you wonders.
Good Luck.
This is the advice you need to follow if you want a good yield. Have you thought about over veging this plant so you can use it as a mother? This is your chance, well you passed it up a bit, but you can go back to a 18/24 light cycle, and turn this plant into a mom so you can clone off of her. GL