Strange sound from 20 week old chicken

[Shaz1522]

Morning.my 20 week old pullet does this honk/cough/sneeze??? sound.
I seporated her from the flock.
She has no other symptoms. I treated her with tylan them worming pellets(also wormed others).
If its gape worm surly it should of cleared after 7 days on worming pellets.marrages with flubenvet. Ive left her on it for 3 extra days up till now
Any idea what it could be.and if i should let her go back with the rest.she has been on her own 3 weeks.
Same sound.no worse no better?
Its only her doing it,i dont know what else to try.shes fine in herself.
Cant see anything in her throat.eyes ckear ,nise clear comb nice and red.not laid yet but only 20 weeks

 

[MROO]

What breed? And I shudder to even suggest this, but ... with a "nice, red comb," are you sure "She" is not a "He?" Try posting some pictures - full on face, head profile and full body profile. I'm sure someone here can verify gender for you.

 

[Shaz1522]

What breed? And I shudder to even suggest this, but ... with a "nice, red comb," are you sure "She" is not a "He?" Try posting some pictures - full on face, head profile and full body profile. I'm sure someone here can verify gender for you.

 

[Shaz1522]

He he/she is x

 

[The-White-Elephant]

He he/she is x

Looks like a male.