It's hard to tell but the two closeups I agree are males.

However, you mentioned the runt, and oftentimes the smallest plants that you perceive as the weakest will be female. That being said though, if you had a choice of several different females, you'd of course pick the most vigorous. So it's very possible your lil one is a girl.

I would either order seeds, get clones, or find some good bagseed now because even if the one is a girl you've still got 9 or so weeks til you can smoke your own!