Don't ever be afraid to say you don't know or you need help. Experienced nurses are more receptive to someone who genuinely wants to learn and seeks their help. And don't exclude yourself at first...
DONT be anxious! You have done this before, the flow of things will just come back to you. Also, if the staff is primarily the same as before you went on leave surely they will have no problem helping...
Also, I'd like to add I'm fully aware of compassion fatigue and that I may sound like I get too invested or emotionally attached to my patients, but I don't believe that's the case. It's usually few...
This may merely come across as a vague "vent" session, I'm more than willing to give more specific details or examples of events to support the feelings I've expressed if anyone is interested/curious...