Hey congrats on your first grow. Someone please tell my I'm wrong, but these seem to have just entered Veg. By my count they only have about five nodes. You should be keeping them in this stage for a while. Much bigger, fuller. Have you even been able to sex them at this stage? I think it usually takes until they are about 12" or so for this to show. Unless these are clones or fem seeds?

But hey I'm only learning as well.

This is a pic of one that have about 5 weeks in.