Advice needed for interview follow up

I interviewed for a job last Friday (12/6) and they said they would be in touch either yesterday (12/13) or today (12/14). I haven't heard anything, but I also know they are a super busy non-profit and things always happen, get busy, etc. and things fall through the cracks. Would it be appropriate for me to contact them inquiring about the position or should I give it a few days?

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official