3rd leaf ?

To me it looks like a male flower starting to form, but without other clear pictures it is hard to say exactly if it is. Sometimes weird growths can grow there, you will know more precisely in a couple of days/bit more growth as to what it really is. Besides, if it were a female flower, two white fine pistils/hairs are usually very apparent, even from day one. In the meantime, you could look at my diary "Cannabis Conundrums" for some pictures of immature male and female flowers and try and identify the weird bits that way. Hope this helps,.. Organoman.

Looks like the start of male or female bits forming. Going far enough into veg, they will sex without you flipping the light.