Welcome To BYC
Can you post some photos?
How old is she?
Have you looked inside her beak to make sure there's no canker, mucous or lesions inside the beak?
Is the discharge clear or does it have a color?
Hard to know if she's got a respiratory disease or if the environment she was in contributed to the symptoms she has. Getting some testing to find out he cause would be ideal, but sometimes that's not possible.
Respiratory disease like Mycoplasma (MG) and Infectious Bronchitis (IB) are 2 of the more common diseases birds can have. Symptoms of MG can be treated with an antibiotic like Tylosin. IB is a virus and it has to run it's course, but sometimes there's secondary infection, so Tylosin may prove to be beneficial for that.