The good: 1) in my experience males usually develop and show sex faster than females. For example, I sexed 16 plants over the last week and and the biggest and first to show were 3 males. Ever since all the rest have been females, with 4 left to sex (no signs yet). 2) balls are easy to spot, hairs not so much.

The bad: 2 1/2 weeks of 12/12 and nothing?

I'd say hang in there a few more days and whip out the magnifying glass. Those hairs can be really hard to spot unaided. Good luck and the law of averages in on your side
R2T