Not to burst your bubble, but that looks a little low to be a preflower. Looks like a stipule, to me. They are green spikes, as opposed to a pod and pistil. Should preflower around 4 weeks veg, give or take.(Seedling doesn't count as veg) I could be totally wrong, just looks like it's below the node, and solid green.
Good growing to you.
Looks like a pistil to me. Stipules like to lay up against the stem.
Pistils are white, stipules are green. I see a white pistil.