We tried to tell our apart at 8 weeks and I was told my roo was a pullet and vise versa. Turns out at 10-11weeks a huge comb popped up on what was supposed to be my pullet. Needless to say, my Rooster is named Pinky!
You may want to wait, but it wouldn't hurt to post some pictures. Preferrably close up on mostly of the face and comb.