I've had a cold for 4 days now, i have a newborn. would she have contracted it by now? am i still contagious?

Cold for 4 days: I doubt you are contagious but please contact the doctor about your newborn (congrats) and your cold!

Still contagious: Hi! the common cold can be caused by a bunch of different viruses; some only take a couple days from time of exposure until symptoms start; others can take up to a week! So it is possible that your baby has already contracted a virus and hasn't yet shown symptoms. Also, keep in mind that you will remain contagious until ~5-6 days after the start of your own symptoms. Hope that helps!