I can't pretend to have all the answers or a ton of experience. I'm just a fellow new grad (May) who started my first hospital job in a 20 bed combined med/surg/neuro/trauma ICU at the end of July. I like the nuts and bolts of things, I love to dig in depth into patho and etiology, and I thought that critical care would fit me.
For sure, it is a steep learning curve going into the ICU as a new grad, one that I recognize I am just at the start of. We have an amazing critical care nurse educator and my organization put me through critical care specific new grad classes that really helped.
I will say this: no one can decide for you if the ICU is where you should or should not be, only you can make that determination. If you are enjoying your work, determined to do the best you can for your patients, and are willing to spend free time, both on, and off shift, researching and educating yourself further in critical care nursing, than there is no reason you can't make it work.
I wasn't planning on starting in critical care, I actually thought I had a cardiovascular progressive care/tele job lined up, but wound up accepting a new grad program here in Colorado. It's intimidating for sure, but that's a good thing: it means you care. I got a little over 12 weeks orientation, take all the precepting your organization is willing to give you.
It sounds like you are with a nurse who is a wealth of knowledge. I know that not all nurses are warm and welcoming, and it doesn't sound like the criticism you are receiving is really fair, but everyone has their own way of motivating and approaching teaching. I would go into each shift with an open mind, prepared as possible, and ask questions non-stop. If it turns out your preceptor truly has a teaching style and or attitude that is hindering your learning and won't budge to fit your learning needs, I would respectfully ask to orient with someone who may be more compatible.
Like someone else mentioned, having the sickest patients on the unit sometimes during orientation is really a blessing. You have a preceptor for a reason: they are there to take the lead when you are over your head, answer your questions, provide back-up, and help you to learn. That's the best possible time to have those patients.
Just know that if you are determined, you can make it work. And truly, you are not alone. I know I don't have all the knowledge I need to have to be a fully competent ICU nurse, but I like to think that if you know when to seek out help and advice from your fellow nurses/charge, RTs, know when to call your physicians, and are dedicated to advocating for your patient and improving every day, then you are making a positive impact and well on the way to becoming a rock star nurse.
Hopefully the ICU you work in has a very team oriented culture. When your fellow nurses are all hands on deck for a new admit or crashing patient, always ready to help you out, offer wisdom, and reassure you, then both the patients, and you as a newer nurse, will benefit immensely and have the best possible outcome. At least that's been my experience.
Take a deep breath and try to learn every day and enjoy what you are doing. As a fellow new grad along for the wild ride, know you're not alone in how you feel. I think if we approach each day with the commitment to better ourselves as nurses, work as a team, and advocate for our patients, everything will turn out alright.