3 almost 4 month old is sick

I’m a ftm, and my little one has a cough and is pretty congested, her 4 month check up is almost 3 weeks out. I have some soothing chest rub along with the vapor Johnston body wash that I’m using should I take her in though because of all the RSV going around or wait it out?

I only ask if I should wait it out because she doesn’t have a fever.