So confused

Sorry in advance for the bad pictures 😒

This chicken is about 4 months old. It was sold to me as a black sex link pullet. The other 2 that came with it look NOTHING like this one. They both have red/copper feathers on their chest and neck. Does anyone know this breed? And of course the age old question is it a hen or a rooster?

I definitely thought it was a hen for a while but then I got confused because it's neck feathers (idk the right terminology) started to get pointy, and idk exactly what to look for with the saddle feathers.