Spit up or throw up?

I have a 5 weeker and I think she just threw up. The nurse didn't seem to worried but still made an appointment today. (I just went back to work yesterday and so I'm trying to get someone to cover my shift today) so she spit up normal, then kinda started choking and threw up some yellow kinda cloudy looking spit up. Since she was choking I had her facing down kinda how you burp them sitting up. Should I be all panicky?? Big brother woke up today (no fever) but a runny nose and bad sounding cough.