Your fine lol. Make sure she truly is broody before you stick Silkie chicks under her. And try and get them as young as possible. I've never done broody hens before. My blind pullet, Amber takes random baby chicks under her wings, but has never tried her hand at hatching. Hazel, my Buff Orphington is attempting ceramic eggs right now, I doubt she will stay at the nest for long.
As for the breed of your hen, she looks like a Maran possibly? Try posting her in the breed or gender section and report back to us so we can assess her potential broodieness. What could egg does she lay, if she has ever laid for you.