URGENT Quail help needed

One of our Quail (a year old) is holding her head over to one side, she is able to stand up if we lift her to her feet but is very subdued and if she rolls over seems to be unable to get back on her feet.  Her five companions are giving her a wide berth (she is upstairs in a coop they have all chosen to stay downstairs although normally they run up and down all the time).  It is possible she has hit her head on the roof of the coop (we are just building an aviary for them as they do fly upwards if startled).  Any advice please?

thanks Kegs, I appreciate you trying to help.  We have brought her inside in a cat box and she is trying to eat and drink but looks very weak.  I spoke to our vet (who very honestly said he had never treated Quail and he would google to see what it could be) he came up with the same suggestion that she is likely to have banged her head and will either have a head injury or concussion which may recover.  He said that most vets would not treat Quail as they are considered a flock and vets are trained to treat a flock if it is commercially viable to do so, but to cull individual birds.  Doesn't help when we get so attached to the little things!

sorry to report that the poor little thing has died.  She struggled to stand all day and although she tried to eat and drink she kept wobbling over.  We had hoped she was just concussed and would become stronger but sadly it wasn't to be. Isnt it strange how attached we become to a small bird!

They nearly have their 6ft tall aviary ready to move into, wish she'd have been able to move into her new home!
Hopefully the other 5 will be very happy in their aviary!