Congrats. on completing your first week. janfrn wrote some good advice as usual
. Be sure to read anything that janfrn posts because she has a lot of knowledge of the PICU and is very smart.
It will take at least a year or two to feel somewhat comfortable in the PICU. I work NICU and it took me years to feel comfortable, but it is a gradual process so as each month goes by it gets a little better. The PICU can be a scary place. I think it would be too intense for me to work PICU. Although I work NICU not every baby in the unit is critical, but if you are in the PICU you are likely to be critical.
Just know that you have a long road ahead of you and to take one day at a time. It will likely get worse before it gets better. I remember a few months into the NICU as a new grad I was seriously considering leaving and working in newborn because it was just so stressful at times and it didn't seem I would ever get it all, but as time went by it got much better and I am very glad I didn't give up.
Enjoy your days off and do fun relaxing things on your days off to regroup and get refreshed.
Keep us updated on your progress and when things get tough come to allnurses and vent. We have ALL been there!