Good Morning and welcome. I am Dr. Loretta, a licensed veterinarian and I am happy to answer your question.
It appears that Sally has a nasal infection that is causing this discharge and this lump is an enlarged lymph node secondary to this infection. If the discharge is only from one nostril, then this may be a mass or tumor within the nose or a gutteral pouch infection causing this. If it is both nostrils, then this may be an upper respiratory infection that Sally is trying to fight off herself.
It is best to have your vet examine Sally if this continues to know for sure.
Does that make sense to you?
Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please Reply so I can clarify for you
Sincerely, Dr. Loretta