Don't stress! Babies know a mothers smell, heartbeat, voice and touch from the moment they are born because they spend 9 months in you! That's why a baby cried when someone else hold them and when you give them back to the mother they stop. You will be just fine.
I'm going to give you a simple answer. You will be fine and your baby will adore you because you are there wonderful mother! No one like you. Keep calm and keep carrying. First time nerves are soooo normal.