Nope, I still think she's a hen, as only female Black Sex-links have reddish feathers. Males are barred. Lots of black birds have some white in them, especially when they are young.
I agree--your chick is most likely a Black Sex-link. Other black breeds include Jersey Giants, Australorps, and Sumatras, but those chicks often have white bellies and chests (which yours doesn't have). When your chick gets older, you'll know for sure--Black Sex Links develop orangish feathers...