They look very good. I would flower now, and go to 12/12 lights. Go to walmart and get some bloom boost by miracle grow (15-30-15) at least to give them some nutes, or check out products from fox farms like grow big, big bloom and tiger bloom. You may wanna give them nutes before changing the lights.
You definately dont need to harvest her yet. Looks pretty good but a few more pics would be good. You need to flush with plain water at least 7 days before you harvest. Gotta keep studying for this final but Ill give you more info when Im done.