Why could my 4 month old Pom started a cough about 4 days ago ?

by Gisel Carrillo
(Dallas, Texas)

Hello, I'am concerned why could my little 4 month old puppy recently started a cough ? We bought her from a breeder 2 weeks ago & she was not coughing at that time. She only had a little bit of runny nose & sometimes a little sneezing; I imagined it would be an allergic reaction to our apartment carpet.
She is an inside puppy & I haven't began walking her out yet.
Still very playful, eats & drinks as usual.
She began coughing about 4 days ago & she randomly coughs not much.
What can it be & what can I do please help.