Help my child has a swollen nymph node middle of her neck it's pea sized and reddish-purple.....home remedies?

She is 5 years old and has had a cough and runny nose lately what concerns me is it appears to be growing and she won't let me touch it...I started a new job and unfortunately Kaiser can't accommodate me with any appointments after 5! How serious is this pls help!!!!!!;(