Serious help needed! Not laying, diarrhoea, runny nose, lethargic

[Chickadee123]

Hi

HELP!!!

I am really worried about my warren hen, she is about 5 months old and we have had her just under 3 weeks.

She laid everyday for the first 4 days, then it reduced to every other day, then 2 days apart and now we are on day 5 since she hasnt laid.

She used to be 'top chicken', but now the other one is taking food off her and she isnt bothered.

She has a gunky nose, diarrhoea, is lethargic, keeps closing her eyes and is really not her self.

Any suggestions??? I am really worried about her

Thanks

Jenny