To go to the doctor or not

My son had had a runny nose for about 4 days and as of yesterday he has been running a fever never higher then 100.7 although nothing is bringing the fever down. I am thinking its just a cold but maybe there's something he needs antibiotics for. And I hate running to the doc spending 30 dollars for them saying it just has to run its course. How long do you usually wait before taking your children in?

if cam just has minor cold symptoms i just let it runs its course unless he has a really high fever that wont go away, or if theres a sign that he might have an ear infection or something since just for a cold they arent going to give any antibiotics

How old is he? Those are symptoms that my son has and his doc said that he's teething and nothing needs to be done unless the fever spikes or he starts to pull his ear. ( sign of ear infection)

He's 10months he was pulling at his ear about 2 days ago but hasn't since