Sexing plants...early distinction...

My plants are showing signs of sex.I proceeded to remove a few that had what looked like lil' pollen sacs to me(was pretty confident in my research)...so I said my farewells and tossed them.....upon reading further haha..I found some things that said early distinction is difficult....oops?some of the pistils on some plants are half an inch long and some are shorter,I'm certain these are ladies.
My question is,how similar do the two sexes look in early stage of showing,and is it common to make the mistake of ditching females because of the wrong diagnosis???I've looked at tons of pics but none of them seem to show me exactly the stage I'm at.They are more developed in the photos and obviously different sexes.

if you have two white hairs comming out of the nodes then its female. either that or you will have a ball thats a male

ok...It's actually white widow,from amsterdam...they were like 60 bucks or something,I assumed it was good to go.So at no point will the growing pistil gland(before hair grows)resemble a little sac or ball and if it does it's male...or hermie??I know it's probably a dumb question but I'm scared I threw out some girls in my haste.I should have let the little bumps develop more...anyway they are gone...I'll let the rest reveal themselves more...thanx!