That's a pre-flower... still may be too soon to call what sex though...
How many plants do you have going?
what type?
So hard to tell, may be just additional growth. Be patient and time will tell, when are you going to start flowering?
yeh man just chill for a bit its only going to be a leaf, you have to atleast wait a week to determine the sex.
and when in dark there should be no light what so ever
light pollution is not good for your plants
good eye for spotting that tiny little thing...
yah man you just have to wait and see
p.s. sick avatar!!