Redd,

It sounds to me like the kitten is feral. Feral cats do not trust humans. They will not let humans anywhere NEAR them. Is the mama around anywhere?? As far as the bobbing of the head is concerned, it's possible that the kitten might've had a lack of oxygen during birth which will cause neurological problems or brain damage. It also may be that the kitten DID get stepped on. The only way you're going to know is to try and get it to a vet or, being that the cat is in a barn (I assume on a farm), see if the vet will make a house call. Good luck. Let us know what happens.

Hear, hear toughCookie!!