Spit up / vomit My lo is 3 days old and when I got up this morning to get her out the crib I noticed…

Spit up / vomit

My lo is 3 days old and when I got up this morning to get her out the crib I noticed she threw up but it was brown. Should I be worried? And now I'm paranoid because she could've choked. I didn't even hear her do it.