Those don't look like preflowers to me - but I could be wrong. They look more like the next set of branches coming out. If you're trying to get them to flower, give them a good 24 hours of dark, and then start your 12/12 schedule.
Yeh I'm on my phone so I can't see the pics amazingly but yeh that's probably what it looks more like.
It's a girl! lol. I can't be sure man. Any little pistols/hairs shooting out of the nodes at all? Looks a little too early to tell. You'll notice two hairs growing out of those little spike things in between the nodes. Don't decide what to keep and throw away just yet. I remember the stress of trying to figure it out during my first grow. You got time, man.
Look with a magnifying glass at them. I usually can tell on the 3rd or 4th week. U can tell between a female or male preflower very easily
You can always use a pair of binocular backwards. Seriously, it works. When you need to check your tricones during harvest time, this works great as well.