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It is not wry neck. If the bird had that they would be off balance and would be turning to one side or the other. Wry neck affects the inner ear balance causing the sideways motion. Rabbits are prone to get it and require antibiotics to treat. I have seen it in Holland Lops & Netherland Dwarfs when I used to breed & show them years ago. It looks completely different than when a Silkie bonks it's head!
You silkie has a head injury. Because most silkies have vaulted skulls they get injuries to the brain very easily. You can give vitamins if you like, you can also give Gatorade. The most important thing is make sure she gets water. The brain nneds time to repair. During this time if she becomes stressed, she will tuck he head between her back legs, walk backwards, and sometimes somersault doing forward rolls. Just help her get to the food & water dish. Most silkies recover in about 2 weeks with no treatment at all. But afterward they will show some signs during periods of stress.
If you go to a show and see a silkie doing a Bobblehead motion constantly, it had a head injurie at some point in it's life. 
Since yours isn't doing the somersaults she should recover quickly. Some chicks get this after hatching when they get pecked on by hatchmates. I raise a lot of silkies and it seems that the better the vault, the quicker they get head trama. I have had many birds recover over night, and a few that took a few weeks. I did not treat them with meds or Vitamins. Just let the body repair the nerve endings themselves. One hen went on to with BV Black at the Ohio National last fall. We retired her after that show, because by the end of the second day at shows she would stress and start doing the Bobblehead thing. Since going into a reirement pen she has never done it again.
Good Luck with your girl!